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If you’ve ever trained a group of athletes, you’ve probably noticed something peculiar. Even though you give the group the same training program, at the end of the training block, there are vast differences in how much those athletes improve.

Some athletes will respond really well to that specific training, and see huge improvements that carry over to personal bests in the competition period. Some athletes won’t respond well at all, and as a result might underperform in the next competitive season. Most of the athletes will show a fairly average response; they might set a few new personal bests and have a decent season, particularly if they’re young and developing, but it might not be anything special.

Over the course of a several different training periods, these effects can add up. Those who respond really well to training will likely compete at a very high level, while those who respond poorly will likely fall by the wayside.

Athletes Are Unique Humans, Not Averages

Anecdotally, almost every coach will have experienced these effects. When I look back to my days as an athlete, I was often in a training group with 10 or more athletes. Yet, in any given year, perhaps only three or four of us would set personal bests—despite following very similar (and in some cases, identical) training programs. I set my personal bests in 2007, and yet was still a competitive sprinter for four years after that. Why I didn’t I improve with more training?

We all know that there is this variation between individuals when it comes to training adaptations, and so it seems odd that there is blanket advice given when it comes to training. For example, the American College of Sports Medicine recommends that advanced athletes use rep ranges of one to 12 in a periodized fashion, with an eventual emphasis on utilizing heavy loads for one to six repetitions.

There are two things we can observe and ask from this. First, that the range of one to six reps is quite wide—would some people be better off working at close to 1RM, while others work at 6RM? The second is that, given that we know there is variation in how people respond to exercise, do such one-size-fits-all approaches, even those with a broad range, create conditions for effective adaptation to occur for all athletes? Inherent within this advice from the ACSM, and similar bodies, is the notion that exercise adaptation is standardized in response to a stimulus, and that if individuals follow the advice, a fairly standardized training response will occur.

This is false.

Instead, there is a wide range in the size of adaptations in response to exercise. This is well-established in the scientific literature in regard to exercise; often resulting in those seeing large improvements being labelled as “high responders” and those seeing smaller improvements as “low responders.”

For example, a paper from 2005 put 585 male and female subjects through a 12-week strength training program. There were huge variations in the adaptations to this training program seen among individuals. For example, muscle size changes ranged from a loss of 0.4cm to an increase of 13.6cm (-2% to +59%). Improvements in the 1RM score varied from no improvement at all (0%) to huge improvements of 250%. Maximum voluntary contraction changes also varied between subjects: Some saw a 32% decrease, while others saw a 149% increase.

This doesn’t just occur following strength training; there have been similar results after aerobic training programs. Perhaps the most famous study to examine this is the HERITAGE (HEalth, RIsk factors, exercise Training And GEnetics) family study. Here, 481 adults were given a 20-week aerobic training program, with their VO_2max tested both before and after the training intervention. The average improvement seen was 384 mL O₂ per minute. However, some subjects saw improvements almost four times this amount, while others showed no improvement. (Some even got worse, although this is more likely due to measurement error or motivational issues than a negative effect of training.)

A large range in variations following training has also been reported regarding fitness improvements after high-intensity interval training, fat loss from exercise, and health-related improvements expected after training—such as an increase in insulin sensitivity, a change in cholesterol levels, and a drop in blood pressure. In fact, this variation is not just seen in response to exercise, but also following the use of a sports supplement such as caffeine.

Inter-Individual Variation in Exercise Adaptation

That there is variation between individuals following training is unquestionable. However, an obvious question remains: What causes this variation? If we could discover and understand the causes of this variation, then we could ensure that athletes undertake training matched to their needs. We could also take steps to change the aspects that lead to sub-optimal improvements following exercise, in order to improve adaptation.

This is the thought process that led me and my doctoral supervisor, John Kiely, to publish our most recent paper, “Understanding Personalized Training Responses: Can Genetic Assessment help?” In it, we aimed to identify the causes of this variation between individuals following exercise (from now on, I’ll refer to this variation as “inter-individual”), focusing on a number of different potential cofounders. The paper itself is available for free, so if it interests you, I encourage you to read it.

As anyone who has ever written a paper for a peer-reviewed journal will know, the process itself is brutal. First of all, you need to fit within a set word limit, which means that many key ideas may have to be left out. Then you hope that your reviewers understand the paper and the point you’re trying to make; if they don’t, then you will have to remove further bits (thanks a lot, reviewer #2). Finally, scientific writing means that you must sometimes use big words and flowery language, which doesn’t always make it accessible to your target audience—in our case, coaches.

Let’s consider this article as a director’s cut version of the paper, where I can explore certain areas in more detail, or provide context that just wasn’t possible within the paper. At all times, you can refer to the paper itself to see how we made the argument in a scientific manner, if you wish. It’s also worth pointing out that we wanted to focus primarily on the biological causes of this variation between individuals. Other researchers have discussed how such inter-individual variation may be partially explained as normal “noise” or error within both a measurement and a population; perhaps the best such paper on this topic is by Atkinson and Batterham. We didn’t cover this in our paper for a variety of reasons, including word limits, but their work is crucial in understanding the statistics behind the individual response to exercise.

The first clue we get as to the biological causes of this inter-individual variation in exercise adaptation is that the individual response to exercise appears to be specific to the type of exercise you undertake. A novel study from 2011 found this to be the case, when 175 males and females were randomized into four different groups for a 12-week training block. One group undertook only strength training, one only endurance, one both strength and endurance, and the other was a control group. As you might now expect, there was a large range in the individual improvements following exercise in all the training groups.

In the endurance group, improvements in aerobic fitness (measured via VO_2peak) ranged from a 10% to 60% improvement. In the strength training group, changes in maximal voluntary contraction varied from a decrease of 15% to an increase of 60%. We might call those that saw a decrease in fitness non-responders, and those that saw improvements of 60% the high responders, with all other subjects spread out in between (although we must keep in mind that some of this is due to daily biological variation and measurement error).

However, it is the combined strength and endurance group that grabs the attention. While some of this group were non-responders in terms of aerobic improvements or strength improvements, subjects did not show a non-response to both. Neither were any subjects in the highest 20% of improvements in terms of aerobic or strength improvements. This means that, while you might not respond well to one type of exercise, you likely will to another. So, there probably aren’t non-responders to general exercise, but non-responders to specific types of exercise.

Why is this a clue? Well, adaptation to exercise occurs through a huge number of different molecular pathways. The signals created by exercise that cause our mitochondrial density to increase as a response to aerobic exercise are not the same as those that cause our muscles to grow after weight training. Instead, variation in these pathways could potentially explain—at least partially—the variation between individuals following training. A number of things can lead to variation within these pathways, but perhaps the most potent of them all occurs within our DNA.

An Essential Primer to Genetics in Sport

Our knowledge of the impact that genetics has on fitness and performance has grown tremendously in recent years. Initially, it used to be thought that perhaps a single gene was responsible for creating elite athletes—known as the “single gene as a magic bullet” philosophy. However, throughout all the research, no single gene has been discovered, with individual genes being responsible for only a tiny amount of the variation between individuals. (The gene with the largest impact that I’ve come across is ACSL1, which explained approximately 6% of the variance in the HERITAGE study, although this has yet to be fully replicated).

Instead, the likelihood is that elite athletes possess a number of favorable versions of genes (called alleles) associated with elite performance. If we hypothetically state that there might be 10,000 different alleles associated with elite performance, we would likely see a threshold, above which being an elite athlete is more likely, although not certain. It is exceptionally unlikely that any person possesses the single optimal genetic profile for elite performance. This was nicely shown in a 2008 paper whereby researchers examined 23 genes where common variation occurs within the population. Even with this examination of an unrealistically low number of genes that might impact performance, the chance of a single person having the “optimum” version of them all was only 0.0005%.

It is very unlikely that anyone possesses the single optimal genetic profile for elite performance, says @craig100m. Share on X

Clearly then, no single gene or even a small number of genes can explain all the differences in variation seen in exercise adaptation. We can therefore state that both exercise adaptation and sports performance are “complex polygenic traits,” comprised of variation in a number of different genes. While it might be easy to write off complex polygenic traits as unexplainable, research has shown that we can start to pin down the genetic variation that contributes to them.

Being an elite athlete is clearly a complex polygenic trait; elite athletes not only have a favorable genetic profile (whatever that might be), but they also often have a good coach, motivation, and nutritional intake. However, a 2007 paper found that being an elite athlete was about 66% “heritable,” which we can take to being down to our genes. Other studies have found that about 50% of variation in VO_2max improvements following exercise is heritable, as is around 45% of muscle fiber type, and 52% of muscle strength scores.

The next step on this journey is to find genes (or more specifically polymorphisms—small changes in the underlying genetic code within a gene that can very slightly change the protein encoded by the gene). A recent review paper reported that there are at least 120 such polymorphisms linked to being an elite athlete, with roughly 10% of these replicated in at least three studies. Research has linked yet more genes, around 250, to playing a role in exercise adaptation.

One of the polymorphisms with the most attention (and, in turn, over-hyped) occurs within ACTN3. This gene creates a protein called alpha-actinin-3, which forms part of muscle fibers. In fact, this protein is exclusively found in fast-twitch muscle fibers, making it somewhat important for speed events. At a certain position in this gene, you can either have a C allele or a T allele. If you inherited one T allele from your mother and one from your father, it is said you have the TT genotype.

If this is the case, you cannot produce alpha-actinin-3. This isn’t uncommon—it occurs in about 18% of individuals—and isn’t associated with any disease. (In fact, some research indicates it might reduce the risk of developing metabolic diseases like Type 2 diabetes.) It does mean that TT genotypes tend to have a lower percentage of fast-twitch muscle fibers than those with at least one C allele. Research also indicates that this can impact the likelihood of being an elite sprinter, with a number of studies illustrating that the TT genotype is uncommon in these athletes. The polymorphism within ACTN3 is just one identified polymorphism that potentially affects athletic performance, with an ever-increasing number of others being identified as research progresses.

The next step is to try to see how these genes influence the individual training response. Sticking with ACTN3, this polymorphism has been shown to impact improvements in peak power and strength following resistance training. The mechanisms by which this occurs are currently unclear, but C allele carriers appear to have greater mTOR activity (the pathway that stimulates muscle hypertrophy) following intense exercise, and also higher testosterone levels—both of which may contribute to the increases in fast-twitch fibers seen. A number of polymorphisms have also been identified that impact injury risk and the inflammatory response to exercise, which may also contribute to the individual variation seen in exercise adaptation.

This isn’t to say that genetic variation is responsible for all the different responses seen in terms of adaptation following exercise; they’re not. A good example of this comes from outside the exercise sphere. We now know that if you give a group of people exactly the same amount of vitamin D, the size of the increase in plasma vitamin D they see varies greatly. Genetic variation in a number of genes helps to explain this, but this variation doesn’t explain all the differences. Instead, we find that baseline levels of plasma vitamin D appear to modify these increases (those with lower initial levels see a greater improvement), as does body mass index. While both additional factors do have a genetic component, they are also subject to non-genetic factors, something which we refer to as “environmental” factors in our paper.

Additional Factors that Connect to Genetics

As a human being, you are unique. Even if you’re an identical twin, the unique situations you are exposed to within your life lead to differences in your “phenotype,” such that you and your twin have subtle differences by which people can tell you apart. The same is true when it comes to examining exercise adaptation.

What we have experienced previously can impact how we adapt and respond to an exercise stimulus, be it acute (e.g., an individual session) or chronic (e.g., a 12-week training program). Our baseline fitness impacts exercise recovery, so that the quicker you can recover from exercise, the greater the likely adaptation you will see relative to someone unable to recover sufficiently between training sessions. Previous training history also plays a role here, with different molecular sequences occurring as a result of exercise in beginners and more advanced athletes. Age also appears to impact how well a person adapts to exercise.

An individual’s nutritional status also impacts exercise adaptation. Different dietary composition of macronutrients can alter the adaptive response, with different molecular signals occurring when an athlete has a high carbohydrate intake compared to a low carbohydrate intake. The same is true for micronutrients. I’ve written extensively for SimpliFaster about vitamin D, and serum vitamin D levels can impact muscle power and force, either in a one-off performance or by modifying the adaptations seen in a longer-term training program. Too high an intake of supplemental antioxidants can reduce the adaptive response to exercise, which I wrote about in “Revisiting the Question: ‘Should Athletes Take Antioxidant Supplements?’” The use of supplements by athletes, such as caffeine or creatine, can alter the tolerable within-session workload, which in turn can lead to differences in adaptation occurring between individuals.

Sports Psychology: Factors That Matter in Training and Performance

Psychological factors can also impact exercise adaptation through several different mechanisms. Exercise is a form of stress, and each person’s response to that stress is highly individualized. Every brain interprets stress differently, with past experiences modifying this response. How our brains interpret a stressor impacts the release of hormones, and these hormones can affect how we adapt to exercise.

A simple example of this is two athletes undertaking a 300-meter time trial in training. Athlete A recently suffered a hamstring injury, and worries about the chance of a re-injury. As such, he is hyper-aware of any symptoms he might feel in that hamstring. The athletes start the time trial, and at 250 meters both are heavily fatigued, with their legs feeling heavy. Athlete A’s brain interprets the feelings of fatigue in the injured hamstring as a re-injury, causing a release of stress hormones, which in turn causes a maladaptive state. Athlete B’s brain, however, interprets the fatigue positively, potentially lowering the stress response and leading to more positive adaptations. My co-author, John Kiely, sums up the impact of stress on performance in this essay, which I strongly recommend you read.

A number of factors can modify this psychological response itself. One of these is sleep, with poor sleep quality or short sleep durations consistently linked to under-performance and under-adaptations in athletes. Lifestyle stress can also impact training adaptations. A study from 2008 found that, following 12 weeks of resistance training, subjects who self-reported higher feelings of stress had smaller improvements in both bench press and back squat compared to those who reported lower amounts of stress.

This individualized stress response can further alter the adaptations seen following a training program by decreasing immunity, increasing injury risk, and blunting exercise-induced performance improvements. In addition to this, within a session the acute psycho-emotional state can impact many things, including within session work rate—which, as is hopefully obvious, can alter the adaptations seen following exercise. All of this indicates that the psychological state of the athlete taking part in the training session and program is an important modifier of the adaptations seen.

An athlete’s view of a supplement’s or training program’s effectiveness can impact their #adaptation, says @craig100m. Share on X

Finally, how the athlete views the effectiveness of a supplement or training program can impact the amount of adaptation seen. This is because previously held beliefs can modify the response a person sees to a stimulus—in this case exercise—through both the placebo effect and expectancy effect. I’ve written about placebo and expectancy effects in exercise before, but in summary, if you believe something will have a positive effect it increases the chances that it will.

A Better Approach Than Trial and Error

Putting this all together, it’s clear that we have genetic factors that influence exercise adaptation, but also a myriad of complex environmental aspects that influence the adaptive response. However, we can add an extra layer of complexity to this because these environmental aspects are partially influenced by genetic variations themselves. For example, some genotypes are more sensitive to stress or susceptible to the placebo effects.

When it comes to subjective effort, this is also partially genetically determined. Nutritional requirements are, too; as I mentioned earlier, giving people the same amount of vitamin D leads to different plasma increases, partially determined by genetic variation. Inherent within all the environmental aspects, therefore, is the pervading influence of genetic variation. Indeed, we can add a further layer of complexity by adding epigenetic modifications—defined as changes in genetic expression without changes to the underlying DNA structure—into the picture. We detail these extensively in the paper itself, and I have previously written about these here.

All of this means that the athlete you have in front of you is a highly complex organism, comprised of their genetic makeup, their life experiences, and their environment. These factors all combine to determine how an individual responds to exercise and, given how complex this is, it should come as no surprise that there is wide variation in the type and magnitude of adaptation seen following training in a group of individuals. If you coach 10 athletes, then you have to deal with 10 different highly complex systems.

Frustratingly, these systems are not stable over time; they constantly change. A simple example of this is vitamin D levels, which tend to be higher during summer months and lower during winter months. If vitamin D can alter the adaptations seen after strength training, then we might expect greater improvements in strength during the summer months, when vitamin D levels are optimal. Similarly, if an athlete has had a successful training block with a coach previously, their belief and confidence in the coach may be higher, which could further enhance the improvements expected from a subsequent training block.

So where does this leave the coach and the athlete? One thing we try to do in the paper is to take this theoretical basis and make it usable. Being able to compete at the highest level is a function of “talent,” whatever that might be, and optimal training. However, the key point is: How do you know your training and lifestyle are optimal?

The usual way to approach this is via trial and error, whereby we try one thing, see how we respond, and then modify it. However, this can be a lengthily process, as feedback in terms of exercise adaptation is not instant. Having more information on which to base decisions regarding training and lifestyle could therefore be valuable.

At present, we tend to gain this information through a number of “phenotypic” tests, which tell you where you are right now. This might be a VO_2max or 1RM test, or a measure of vitamin D in the blood. This can lead to the use of training methods to improve those physical metrics, or supplements to improve the dietary aspects. The problem with these tests, however, is that they have minimal long-term predictive ability.

If my vitamin D score is currently X, how do I know what I need to do to get it to Y, given that there is so much variation in individual responsiveness to vitamin D supplementation? The same is true for training; while my current bench press 1RM might be 165kg, what type of training do I need to follow in order to get it to 200kg? While we might follow the usual guidelines, I’ve already discussed how the variation that is inherent in each person means that these guidelines probably aren’t optimal for each person.

The Future of Genetics and Genetic Testing

Given that genetic factors are the reason for a large proportion of this variation between athletes, the possibility remains that we could test for these factors in order to provide more information. This is currently an emerging field, but there is some evidence that genetic testing may hold some predictive ability in terms of exercise adaptation, although not all researchers share this belief. What is clear is that we cannot use genetic testing as talent identification (something that I discussed previously).

There are also many ethical hurdles that require negotiation before genetic testing within sports will become mainstream; nevertheless, the promise remains that, as more research is carried out, genetic testing may yield information that we can use alongside, not instead of, more traditional testing procedures such as physiological or blood tests. This is an area I hope to explore further in the future, so watch this space for updates, and, if you’re a coach of athletes interested in taking part in this research, please get in touch.

Thank you for taking the time to read through this article on my first paper as lead author. If you’ve enjoyed it, or at least found it interesting, please check out the full paper itself, along with our other work, as it contains much more information.

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Intensive squatting provides many benefits for athletes and serves as a foundational movement for athletic performance. Increased cross‐sectional muscle area and changes in neural drive will not come from a diet of goblet squats and Bulgarian split squats. In a previous article, I argued that heavy single-leg work offers tissue adaptations, but there is something about bilateral work that offers greater neurological stimulus. This may be because bilateral velocities overall seem to be faster than unilateral velocities, especially from deep positions with high loads.

The Return of Intensive Squatting

To clarify, we’ll regard the definition of intensive squatting as anything over 90% of an athlete’s 1RM. This can be a contentious issue, and some coaches avoid intensive bilateral loading; heavy bilateral work can be challenging. Much of our approach and orthodoxy is borrowed from lifting sports where the specific expression of strength lives at 90%-100% loading and the athletes involved have anthropometries suited to lifting.

Often, athletes who possess leverage great for sport have poor leverage for lifting. And under high training loads, they exhibit high peripheral and central nervous system fatigue. Both of these will impact heavy squatting. Another oft-repeated concern is lumbar stress which may be a problem if lumbar flexion and/or excessive forward leaning occurs with high loads. However, lifting 90%+ has too many benefits to ignore and should be integrated into physical preparation where applicable.

Video 1. Intensive training at near maximal thresholds creates unique adaptations to the nervous system. The brain is challenged just as much as the muscular system, so proper loading is essential to stimulate growth and recovery.

Heavy squatting has several systemic benefits that are hard to achieve with lighter loads. We see improved recruitment of muscle fibers–in particular, heavy squats recruit and activate the maximum number and the fastest motor units. Improvements in the underlying neurology of strength expression such as rate coding/firing rate or discharge frequency are long-term adaptations caused by heavy strength training.

We also see improved intramuscular coordination and muscle fiber synchronization relating to the pattern by which fibers are recruited. The greater expression of intramuscular coordination improves muscular synergism. Finally, this type of training boosts serum testosterone levels.

Reconciling these benefits with an athlete who may have a busy schedule and high training volumes can be tricky for coaches. We can, however, manipulate things a little to provide intensity, keep volumes appropriate, and make changes to minimize technical aberrations. The key is to apply stress in a fashion that yields benefits and mitigates drawbacks. If this has to bend orthodoxy slightly, then so be it. We can provide this in the form of derivatives, clever rep schemes, and load manipulation.

How to Insert Clusters into Training

Clusters, which seem to fall in and out of popularity, make for a safe and effective way to integrate volumes with high load levels. Tufano et al., 2017 established that a large body of evidence supports using cluster sets to maintain or increase acute power-related variables, such as jump height.

By using clusters, we can sustain higher velocities in our final sets than we can with tradition set and rep schemes. The method simply calls for short inter-rep rest periods between sets. For example, perform one rep at 90% of 1RM, rerack, rest 15 seconds, and perform another single rep.

With cluster sets, we can focus on form while maintaining velocity and power output (Nicholson et al., 2016c; Tufano et al., 2017). This, in turn, allows for a greater volume of work at higher intensities. We can moderate the volume with a velocity-based drop-off between reps to keep quality as high as possible. We use a 5-10% drop-off.

Clusters at 90% of 1RM are best employed as doubles and triples–while remaining cognizant of quality at all times. There are numerous ways to sub-set rest periods for cluster work, including straight reps with a single cluster. For example, perform two conventional reps, rest 15 seconds, and perform a final rep.

Clusters moderate poor final reps due to #fatigue, especially for high-load front squats, says @WSWayland. Share on X

Fatigue causes a lot of poor final reps, and clusters are one way to moderate its effects. From a personal coaching standpoint, clusters are particularly beneficial for front squats at high loads where fatigue can compromise the rack position.

Implementing Death-Ground Squats

Effectively a cluster variant, our death-ground squat parameters are:

• Squat at 90%+ load every minute on the minute (EMOM) until we see a degradation in rep speed and movement quality.
• Across an array of athletes, most can achieve 5-8 reps with 1:00-1:15 rest between reps.

Why perform repeated singles? With high reps and high loads, the neuromuscular system fatigues to the point where a second set will not resemble the first.

Why rest 1:00? It’s enough time for the CP system to recover while keeping the nervous system in an excited state without the energetic cost of multiple reps with only limited rest between clusters. It’s a very time-efficient way to develop skill and capacity. You have about six seconds of quality, very high-intensity work available. Go beyond that, and we start using energy pathways we should avoid and see a speed and nervous system degradation.

Video 2. Low reps are great for athletes, but we must manage them carefully as they are exhausting to the nervous system. Avoiding intensive training will only dig an athlete’s grave later in the year; sufficient maximal strength drives the lower body’s power.

By hitting regular singles much like the cluster sets, we can achieve a higher volume of high-quality work at a high intensity. I find that attempting 90%+ lifts using 3 x 3 leads to an awful looking third set, despite Zatsiorsky suggesting this is the best place to acquire strength in the classic Science and Practice of Strength Training. While this might be fine for Soviet-era weightlifters practically, applying it to sports athletes is a tricky proposition. I’m sure any strength coach would rather have nine high-quality reps than three good ones followed by six ugly ones.

To dictate the amount of volume achieved, we use a timed drop-off, a velocity measurement, or a coach-determined drop in rep speed. There are plenty of inexpensive velocity measurement tools, some of which offer percentage drop-off alarms. We usually look for a 10% drop-off in speed or power.

We often find that the first rep is slow and subsequent sets are faster until, on average, reps 6-8 unless the athlete is having a really bad day and achieves only 3-4 reps. Load and the athlete’s activation/arousal matter.

We can also apply this in an EDT fashion, setting 15-20 minutes aside to perform as many singles within the prescribed time or until a velocity drop-off occurs within the time limit. The athlete’s goal is to increase the total number of reps performed within the time limit.

This works well with high-functioning athletes who can perform 90%+ squats for numerous reps. Most athletes don’t have time to perform at least 20 reps of squats because it would leave little room within their training session for anything else.

Hand-Supported Squats: From Basics to Mastery

Recently I explored heavy Hatfield or hand-supported squatting. I discussed implementing this method in a previous post as a hand-supported split squat. High loads are quite achievable with this method. Adding hand support increases stabilization, allowing an athlete to provide a maximum effort through their legs.

Increased intensity and decreased risk while moving very high loads at high velocities make this appealing, and it can do much for building confidence under big weights. It gets a lot of traction particularly with my tallest and heaviest athletes who seem to get much more out of hand-supported squats than my shorter athletes.

Hand-supported squat increases intensity, decreases risk while moving very high loads at high velocities, says @WSWayland. Share on X

We must not, however, use it as a crutch for squatting. It’s best used with athletes who have well-established competence and strength in the squat pattern. I’ve had to chide assistant coaches at my own facility for being keen to get clients lifting with hand supports before establishing a strong conventional squat.

• Encourage an athlete to stay tall and use the handles for support.
• Staying tall minimizes forward lean and lumber stress, and the safety bar takes out the more problematic elements of heavy axial loads.
• The athlete should push-off only when using eccentrics or isometric methods.

This method is also useful for contact athletes who have elbow, wrist, or shoulder injuries and may struggle with conventional squatting positions.

To program the hand-supported squat, I usually suggest 20-25% more weight than an athlete’s back squat 1RM. I employ two variants depending on whether the athlete needs more knee extension or hip extension:

• Hip dominant hand-supported squat
• Quad dominant hand-supported squat

Integrating Bulgarian-ish Squats

I use an auto-regulatory method for athletes with high training loads, particularly in-season, that I call the Bulgarian-ish method. I apply this only once a week rather than every day as per the original method.

Simply, the athlete works to a maximum single rep for the day. You can use velocity threshold to dictate how heavy the athlete goes, and building an individual velocity profile can be useful. But I find 0.25 m/s average for back squats and 0.3m/s average for front squats works really well. The aim is to work up to a comfortable heavy single.

Adding volume is simply a matter of dropping 10-15% of your daily maximum and doing a few sets of doubles or triples. Any attempt to add more volume will usually end in disaster. I only back off sets on the day I feel capable. Controlling your ego is crucial.

The following example presents a threshold of 0.25m/s.

I find this method highly beneficial from a psychological perspective because it allows athletes to come close to their maximum in a controlled fashion. It re-establishes that they are not stepping backward regarding their strength, offering a boon mentally.

It’s very important to restate that this is not an opportunity to go for a 1RM every time we use this method. I’ve had athletes sheepishly admit that they couldn’t resist the temptation to go for a new one-rep maximum when left to their own devices, usually when a coach wasn’t present. I’ve had athletes hit personal bests in training and established a new 1RM staying out of velocity threshold. It’s great if this happens, but it’s not the goal.

Partial Squats

Pervasive thinking in fitness has damaged the reputation of partial squats. I’ve heard strength coaches, athletes, and personal trainers screech about “ass to grass.” The depth conversation has been done to death, and it’s not what I’m addressing here.

As a culture, some coaches have a hard time with the partial squat as a tool due to the “squat deep” mantra that’s become deeply ingrained. This makes little sense in a world where the trap bar deadlift has been embraced wholly–ostensibly a partial squat but with none of the benefits of a heavy squat–which Carl Valle illustrates in this article. Don’t throw the baby out with the bath water. Put the much-maligned partial squat in your toolkit and use it.

The partial squat allows greater force and power outputs. Put it in your toolkit and use it, says @WSWayland. Share on X

From a research standpoint, partial squats have received a reprieve with studies demonstrating its benefits. The usefulness of the partial squat comes from accelerating high loads at high velocities, which allows for greater force and power outputs, according to a Drinkwater et al. study, 2012.

To quote Chris Beardsley discussing a Bazyler et al. study, 2014, “Partial squats may have applications for improving maximum full squat performance, possibly because heavier relative loads can be used for the same number of reps when working at shorter muscle lengths.” Greater intensities for more reps reflects the thinking we apply to clustered squatting.

Another option is the sports back squat, a narrow stance partial squat discussed by Cal Dietz in his book, Triphasic Training. The aim is to take the hamstrings to a parallel position.

The thinking is that “athletes don’t need to keep working on hard, straining, maximal effort lifts in very wide stances. We want explosive, reactive athletes who can generate huge forces quickly in the direction where their sport will likely be played (i.e., narrow stance).” We see the same thinking in the Bazyler study concerning the need for force generation.

Key technique uses the agonist and antagonist muscles most effectively. Athletes pull themselves into position using their antagonist musculature–the hip flexors and the hamstrings–and explode back out again. I usually encourage this technique for all squats my athletes do.

We often see people perform partial squat off pins. While useful for powerlifters, this isn’t the most productive method because it lacks the return of force and the switch from eccentric into rapid concentric action. It’s the same reason I prefer Romanian deadlifts over rack pulls.

Partial squats should be included in programs when athletes have a decent level of strength and have performed full range of motion squats. Provided you choose appropriate ways to implement a partial squat, it provides a powerful stimulus for great levels of power and force production. I find it particularly useful as a heavier in-season option as it offers a lot of stimulus without a lot of tissue perturbation.

Putting It Together

Intensive squatting for non-lifting athletes has many benefits. Understandably, some perceive it as dangerous and fraught with risk. We know, however, that this kind of stress builds robustness and resilience that we can’t find under an upturned kettlebell.

To integrate intensive squatting into a program, I plan a 90%+ squatting option at least once a week during our heaviest lifting cycles. Below are some weekly sample programs showing how to slot 90% squat options into a program.

There’s no reason why we can’t apply some of these 90% options to other movements such as the press or deadlift. These have their own constraints and limitations, however. For instance, 90%+ deadlifting can be extremely taxing neurologically, not benefiting from a stretch reflex, unlike the squat pattern.

Future Considerations and Suggestions

Running off-season programs presents ample opportunities to implement intensive squat work. For advanced athletes, it provides an opportunity to express their highest levels of strength in a manner that yields improvement but errs on the side of caution. Trying to put non-lifting athletes through a conventional intensive squat program is a fast way to burn them out. However, manipulating movement, load, and volume at high intensity will hopefully keep athletes safe and improved.

Since you’re here…
…we have a small favor to ask. More people are reading SimpliFaster than ever, and each week we bring you compelling content from coaches, sport scientists, and physiotherapists who are devoted to building better athletes. Please take a moment to share the articles on social media, engage the authors with questions and comments below, and link to articles when appropriate if you have a blog or participate on forums of related topics. — SF

In-season training at the collegiate level is a balancing act between player development and team success. On the one hand, you are dealing with 18- to 24-year-old athletes in the prime of their physical development life. The physiological progress that is possible with this specific population is about as good as it gets, on paper at least.

On the other hand, when you work in the collegiate setting, especially when you are on staff with a specific team, the primary goal of everyone associated with the program is to find a way to win games. Player development matters according to the program, dependent on team culture and provisionally on buy-in or emphasis by the head coach/GM/check writer. Regardless of the situation you find yourself in as a performance coach, a balancing act must occur in order to optimize both sides of the coin. If done right in a model that values high performance, you can optimize readiness and sport performance, while still allowing for technical, tactical, psychological, and physical development over the long haul.

Balancing the Goals of Winning Now and Long-Term Development

The key to successfully walking the tightrope between long-term development and short-term success lies, of course, in great communication and collaboration, in an environment devoid of “silos,” where everyone is on the same page. This admittedly “unicornian” example of a perfect scenario probably doesn’t ever completely exist, but in a setting where all parties at least continually strive to reach excellence, high levels of sustained success become the standard, rather than the exception. It is within this model that we, as performance coaches and sport scientists, hope to operate, while managing the bumps, bruises, fatigue, soreness, and monotony.

My current setting is a system that we have grown and developed over time, and it is a mixture of communication, trust, science, art, love, accountability, and a shared desire to continually improve. There is no “one thing” that we do that is the answer to the riddle of managing athletes from a development perspective and, at the same time, ensuring that performance capabilities are high week after week. Instead, we have a holistic model that attempts to encompass multiple factors and eventually allows for more informed decisions by all individuals involved, as to what the appropriate action might be at any given time. This isn’t to say everything is smooth sailing, that wins and player development come easily, or that there aren’t bumps in the road. The reality is that these things get harder and harder to achieve over time, but I can say without a doubt that our expectations are high and our standard is passed down and pushed up year after year.

Creating a Real-World Monitoring System

The process by which we operate has several different components, all equally important to the whole and none more important than the other. What we do from a physiological as well as subjective monitoring perspective allows us to better understand the stress we apply to our athletes, and how they adapt (or don’t). It provides context and color to the ever-looming debate over how much is enough, whether more or less is better, and what the physiological result of our training and competition actually is. It informs, but does not dictate, future action. “Front end monitoring” as we call it, simply provides information.

Athletes don’t care how much you know until they know how much you care, says @DMcConnell29. Share on X

Most importantly, this first layer of data allows for conversation, both with the athletes and within the staff. Nothing creates more buy-in with an athlete then them believing you genuinely care and have their best interests at heart. Difficult conversations that come from a place of mutual understanding and trust can have broad and deep positive implications. They don’t care how much you know until they know how much you care.

A standardized, consistently applied, subjective questionnaire is the first line of defense in our front end, allowing us to gain insight before training or practice on a daily basis, as well as identify any red flags that warrant a follow-up with the athlete. This might be the simplest and most important piece of data that we collect, as it gets us real-time data that we use to make acute adjustments.

The next layer in our attempt to quantify stress and the resulting adaptation—and ultimately navigate the inevitable bumps, bruises, and fatigue—is to utilize HRV daily. This allows us to gain a wider view regarding “readiness” by gathering information about the relative state of the autonomic nervous system. We don’t make rash decisions based solely on HRV readings on a day-to-day basis—there is too much noise in the signal with our setup.

While we are consistent and have a standardized protocol, the reality is the data we gather can never be completely clean. This is because it happens in a group setting in our Hockey Performance Center, sometime after the athletes have gotten out of bed and made their way to the arena. That being said, the data remains valuable over the long term from a trend analysis perspective, and adds a layer of feedback on top of our subjective data to evaluate adaptation. Just as importantly, it sparks conversations with the athletes when necessary.

Creating a Routine and Readiness to Train Workflow

The last layer on the front end is simply having the athletes weigh in every morning. This basic, time-tested routine provides a myriad of benefits. First, it allows me as the coach (and the athletes individually, once we’ve educated them) to monitor hydration status simply by referencing the previous day’s weigh-out number. The athlete should return to the same weight as the previous day; if they don’t, they have not taken the necessary steps to rehydrate since the last physical event.

Having athletes weigh in every morning is a time-tested routine with a myriad of benefits, says @DMcConnell29. Share on X

Second, it obviously provides long-term trend data on weight gain or loss, either of which may be positive or negative depending on the athlete and the situation. And third, weighing in daily emphasizes to the athlete the importance of body composition and hydration over a long and grueling season. As Dan John has said, “If it’s important, do it every day.”

The last piece of the front end is to utilize RSI as an autoregulatory tool. This approach is by no means foolproof, but it has proven to be a reliable workaround in our setting to objectively quantify CNS “readiness,” while at the same time appreciating individual differences in workload and overall fatigue. In a nutshell, we use the RSI score from a drop jump prior to lifting sessions to adjust the loading our athletes will perform.

Based on a 30-day rolling average, if an athlete’s current RSI score is more than a .5 standard deviation above their norm, we assume that they are “well recovered” and that their system is in a good place to push development. Those athletes scoring above this threshold will increase the load in their primary exercises for that training session by 10-20 pounds. If they score within their “normal” range (within .5 to -.5SD), they will simply continue to train off their prescribed percent of 1RM. If they are below .5SD, they will cut some volume, as we take that score as an indicator that they are not firing on all cylinders and today might not be the best day to hit the gas pedal.

Psychology trumps physiology every day, says @DMcConnell29. Share on X

The caveat to this is that any athlete who scores in the “Red” must first talk to me before adjusting their loads. If they tell me they feel great and don’t want to cut anything back, I will more than likely honor their desire and allow them to train as normal. Psychology trumps physiology every day. I want to cultivate a culture of effort and accountability, and if an athlete wants to get after it, I will probably celebrate that.

Back-End Analysis for Strength and Conditioning

The flip side of “front end monitoring” is “back end monitoring”: gathering, analyzing, interpreting, and understanding the data we collect from a physical output perspective. This gleans invaluable insight into the response to training and competition. If all stress is stress, it is imperative that we measure what we can to try to better understand the implications, so that we can improve our future application of that stress.

The back end is about finding out what happened. Without this layer, load management would simply be a guessing game. This can come in many forms, both subjective and objective, shorter and longer term. Daily sRPEs alongside internal training load measurements like TRIMP and intensity density provide a window into physiological load, and the athlete’s ability to handle it. These metrics should somewhat mirror each other: hard days should feel hard; easy days should feel easy. Mismatched trends can indicate functional overreaching if necessary and appropriate, or warning signs that the balance between developmental desire and performance necessity may be off. 

Longer-term indicators of global strength and power development, as well as fatigue and readiness balance, are also important. We use various vertical jump metrics on a continuous and rolling basis across the season, not only to provide important data about developmental trends, but also to allow for more nuanced training within the team setting regarding individual make-up and needs. Non-counter movement, counter movement, and drop jump/RSI scores paint a picture of the relative strengths and weaknesses of each athlete. You can build a “jump profile” from this data, which will help to direct training in the appropriate area.

Weekly acceleration-based speed assessments not only microdose all important high-velocity movement—crucial to applying appropriate stress outside of competition to remain capable of handling those loads within competition—but also create and take advantage of the athlete’s competitive drive, fostering a culture of effort, excellence, and grit. Nothing gets a competitive person more excited to give a maximal effort in the dog days of mid-season training than sprinting against the clock, with teammates cheering and chirping, with past and current times posted for all to see.

The Programming of Strength and Conditioning

As we slide down the continuum from monitoring to training (they are really all one piece of the same pie, and so cannot be completely removed from each other), we arrive at loading for development and loading (or unloading) for immediate performance. This is where the meat and potatoes of the balancing act come to the table for the performance coach. Monitoring gives us information, and now we must use that info to make decisions.

Culture must be the first part of this conversation. Nothing even remotely appearing to drive development or reach optimal performance is achievable without a culture cultivated from the top down and reverberated from the bottom back up, that emphasizes, demands, and embraces effort and intelligent training. However, when this is the standard held up within a program or organization, it is up to the performance coach to appropriately guide the athletes towards this goal.

I am a firm believer that strength must underpin and set the foundation for high performance development, as well as athlete robustness, in team sports. Actual weight room loading must progress in intensity and then remain high. Consistency is key: Once the foot is off the gas pedal in-season, it’s nearly impossible to get back up to speed.

Athletes must routinely use loads between 80% and 90% to provide adequate stimulus to the organism and ensure the ability to maintain the expression of this level of force production. That said, I favor a very low volume approach. At no time in the season should there be an overload of volume or a “straining” or “grinding” to the movements of training. That is why consistency is so key. More than a week or two away from heavy loads will result in a marked increase in effort, and a decrease in velocity, of the primary exercises.

There is, of course, a time and a place to taper load and increase velocity, but I find it best to reserve this for a very narrow window at the very tail end of a season. If 85% of a rear foot elevated split squat for two reps is hard or nearly impossible late in the season, then you, as the coach, failed to apply adequate stress long before that.

Fine-Tuning the Weight Room with VBT

One tool that is a “nice to have”—but might just be a “need to have,” if at all possible—is something that allows for velocity-based training. VBT lets us autoregulate loading, but in a much more nuanced way than RSI. This is nothing new, but when it comes to managing stress and fatigue, and bumps and bruises, the ability to prescribe training by speed instead of load, and the subsequent ability to adjust sets based on an athlete’s acute abilities, is hugely beneficial.

The key is getting athletes to respect the numbers, and back off when the data says back off. At first, this is tough, as they won’t feel like they’re getting better. But over time, with enough education and buy-in, they will realize that following their nervous system’s ability, which is really just listening to their body, will result in one step back and three steps forward.

Mastering the Balance and Using Common Sense

At the end of the day, the balancing act between longer-term athlete development and shorter-term team success comes down to managing stress. It’s like Goldilocks: not too much, and not too little. Finding that sweet spot is a combination of art and science. A coach’s intuition, along with candid conversations with the right group of players, is a must, but so is the appropriate use of objective data. “Figures lie, and liar’s figure” might be true, but data can still tell a story.

Balancing long-term athlete development and short-term team success comes down to managing stress, says @DMcConnell29. #LTAD Share on X

There is no one thing, no unicorn answer, to tell you how to navigate a long season and maintain equilibrium between development and readiness. Furthermore, no season is the same. But hopefully, in the quest to achieve this goal, common sense backed up with a little bit of science will be the winning recipe.

Since you’re here…
…we have a small favor to ask. More people are reading SimpliFaster than ever, and each week we bring you compelling content from coaches, sport scientists, and physiotherapists who are devoted to building better athletes. Please take a moment to share the articles on social media, engage the authors with questions and comments below, and link to articles when appropriate if you have a blog or participate on forums of related topics. — SF

After 20 years of scientific research, we are closer to knowing how isoinertial training works, but we are not much better at knowing how to plan training sessions. Some studies have done a great job of comparing flywheel training, a type of isoinertial resistance, to conventional training, but they have not presented anything in enough detail to satisfy the practitioner. This article is not about just a single approach; it’s about learning to use flywheel training in a way that is meaningful and purpose-driven.

The Most Common Errors In Flywheel Training

While not truly a mistake or error, the most common approach to flywheel training is to replace exercises done on the ground with a flywheel alternative. While swapping modalities that are similar makes sense on paper, contractions are not about visual similarities. Instead, they are about the roles and needs of preparing the body based on the inevitable calendar of training and competition.

Just adding a few sets of popular #flywheel exercises like a dash of salt isn’t great programming, says @ShaneDavs. Share on X

Switching a barbell back squat with a flywheel squat isn’t a pure replacement, and just adding a few sets of popular flywheel exercises to a program like a dash of salt isn’t great programming. Based on common patterns of use, most of the approaches we have seen with flywheel integration are:

• Add in a few exercises at the end of a conventional program as a finishing option.
• Replace traditional exercises like barbell or bodyweight movements with flywheel variants.
• Add a flywheel phase of training with a heavy concentration of isoinertial training.

These approaches aren’t foolish, and we have experimented with similar tactics, but we can do better. The No. 1 issue with any modality is that the best coaches usually have very little bias towards any method, as they simply want what is effective.

What we rarely see are long-term records of research-grade measures of real athlete training. Most of what we see in the research are general populations or short intervention studies; nothing replicating a four-year development plan for serious athletes. Coaches need science, but they also need complete history or record-keeping for the big, integrated picture. Science is our best tool, but don’t underestimate that interpretation of the science has even more importance because reasoning is what makes knowledge useful.

With the errors above in mind, we will show how you can modify training to integrate flywheels without the mistakes that are commonly made in programming.

Don’t Think Movements, Think Contractions

The functional training craze of the late 1990s did have value—it made us think of what the word “function” really meant. Mimicking sport by recreating similar motions isn’t functional or sport-specific: it’s usually just a really bad attempt to combine weights and athletic motions. We have seen countless exercises come and go, while other exercises seem to linger longer. Shadowboxing and running with dumbbells are still popular, but so far nothing in the research shows either is the magic bullet. When thinking functional, don’t focus on what the exercise looks like, appreciate what the training gives you back.

When selecting exercises, it makes sense to think about the mechanics of the movement, but the contractions are still different than traditional barbell or bodyweight motions. It also makes sense that a similar exercise of the same “species” will be a logical exchange, but the way flywheels work, some adjustments to the entire program are necessary. For example, if you take out barbell back squats and switch them with a platform flywheel, the result is much different.

• Barbells can do low or single rep ranges; flywheels need starter reps to initiate full isoinertial reps.
• Between repetitions barbell options allow rest, while flywheels are constant effort contractions.
• Flywheels have high inertia immediately during the descent of exercises, barbells don’t.
• Using a waist belt reduces overall spinal loading, which is a popular rationale for coaches who need that requirement. 

We could go on, as there are more differences than those listed, but the swapping out of an exercise is not a pure exchange. There are enough differences that coaches must make more changes than just the exercise name on the workout sheet. The No. 1 takeaway is that swapping out an exercise usually has a ripple effect in training. This means that you might have to adjust other parts of training during and after the sessions to accommodate the differences.

The No. 1 takeaway is that swapping out an exercise usually has a ripple effect in training, says @ShaneDavs. Share on X

How to Use the Molecular Signaling of Flywheels

We could name a few coaches that hate the concept and even the word “finisher,” but tacking on a few sets at the end of a training session isn’t the end of the world, and does have some benefits. Training is tough physically and mentally, and just a little dessert here and there isn’t going to ruin someone. This article briefly mentioned the idea of using flywheels and finishing a workout with isoinertial training, but it’s more than just doing a few sets of an exercise at the end of a workout. It’s about the molecular responses.

What we know about molecular signaling and training is that low loads and high repetitions can stimulate both strength and size. Some current unfounded fears over having the wrong morphological changes are that the specific muscular adaptations from lower loads increase the wrong type of hypertrophy. Simply stated, high reps theoretically build less-favorable changes to the tissues for athletes because it’s just “body builder” muscle and has a poor power-to-weight ratio.

At the molecular level, flywheels may be the most potent way to increase muscle’s strength and size. Share on X

To date, research has not shown conclusive evidence, because nearly every training program has maximal effort bouts in the workouts. Blood flow restriction training maximizes high repetition training, and flywheels tend to be higher repetitions as well. At the molecular level, flywheels are likely the most potent way to increase the strength and size of muscle.

Theoretical sarcoplasmic and myofibrillar hypertrophy debates have been going on for years, but we don’t think it’s a concern if the concept is proven true. Remember that the discussion is about the singular and pure modes of training; meaning the difference between a full-time bodybuilder and a full-time power lifter, not an athlete using mixed and multiple methods. In theory, so much of the training is one style of lifting that the long-term training effects should induce clear differentiation. We don’t see classification of athletes based on sport (powerlifting versus bodybuilding) now as much as we did in the earlier hypertrophy research because many athletes overlap their training programs.

Most of the training of flywheels is eccentric enhanced power and strength development, due to the load and speed of the contraction. The research concludes that hypertrophy from flywheel training is very potent, and we have witnessed exactly what the scientific investigations claimed—rapid changes in cross-sectional area or CSA. While training for muscle mass isn’t a direct way to get faster or decelerate safer, many athletes that we inherit have atrophy from injuries and we need rapid changes to get them ready for another year of competition. There’s a growing need to fix muscle groups that are legitimately shut down due to non-use, abuse, or lack of proper rehabilitation. Poor development of youth sport athletes by selfish coaches is the cause of this problem.

In theory (but supported by enough research to make a case for flywheels), if you want to send a very strong message to the muscles of athletes, use flywheel training because it combines multiple factors that target the molecular pathways to grow and get stronger. The moderate load, constant tension, and depletion style sets are the reasons we add one or two exercises at the end of training. We adjust our program, not by decreasing volume, but just scaring the athletes into being receptive to getting more sleep and taking responsibility for their diets. Flywheel training isn’t for everyone and that is a good thing. Athletes need to deserve it first, by making the sacrifices and commitment necessary to recover from it.

The Keys to Constructing Concentrated Eccentric Phases

The terms “block” or “phase” get kicked around easily, but for real adaptations to occur, a signal to change the body must be clear, intense, and frequent over time. A soon as a phase ends, detraining effects of that adaption will occur unless it’s sustained by a signal that is either the same or very similar. Debates will never end on which are the best roads leading to Rome, but it’s easy to determine success. Mechanical strength and structural length are two near bulletproof measures that determine the success of an eccentric program. While ultrasonography measures are not easy to capture, we do know that specific exercises elicit the changes we all need for athletes. Neuromuscular strength is direct and easier to see trend, as all it takes is a workout session to evaluate.

Heavy eccentric training is brutal on the body, and recovery from that type of resistance requires time. Additionally, eccentric training is very selfish, meaning not a lot of resources are available to develop other qualities needed in sport success. Hence, eccentric training isn’t the ideal way to build athletes in modern sport when the checklist already has so many much-needed items to develop. Realistically, eccentric overload time periods are sessions rather than months. As few as three weeks are enough make serious changes to the neuromuscular system. About 10 to 12 aggressive sessions that push an athlete will make all the difference for a season, and improvements can reap benefits later if you continue the training in a reduced fashion.

A phase of training should never require more than a few days of #recovery, says @ShaneDavs. Share on X

With added eccentric training comes muscular, and sometimes tendon, soreness. Incremental loading and careful monitoring are essential or the result is just a tired and beat-up athlete. We have yet to see an injury from eccentric training when loads are based on reasonable adjustments, but we have seen plenty of athletes stagnate (including our own) from “too much, too soon” loading. Exactly how much overreaching happens with eccentric training is unknown and will vary from program to program, but a phase of training should never require more than a few days of recovery.

We have been very liberal with nutritional practices, meaning we don’t try to have an athlete decrease their body fat by reducing caloric intake during eccentric training phases. During the winter offseasons for football or late fall and early summer breaks for soccer, we don’t stress about athletes not being strict with their diets. It’s not that we allow poor eating habits, it’s just that we would rather have more work to do later when we have conditioning than make the mistake and under-recover them because we had insufficient calories too early. Eccentric training has no reported research that claims extra protein or nutrients are necessary, but we don’t want to make the mistake and not have enough. We can’t go back and fix the problem, but we can address body composition more easily and manage it immediately.

The recovery support, or what we provide athletes with, during heavy eccentrics are hydrotherapy, EMS, and some massage. Even if an athlete just tacks on a few sets of flywheel training at the end of a program, it’s enough to warrant an adjustment to the recovery side or low-intensity parts of a program. Some will argue that we should save recovery for later periods, but we care about deeper preparation levels with strength so we can train harder mechanically.

Physiological fears of blunting recovery internally are more for cryotherapy, an approach that should be for peaking periods. Besides time and soreness, be vigilant for residual fatigue and emotional darkness (poor willingness to train or worse). Athletes will lose their drive and motivation when training during heavy periods, so don’t just look at training data.

Progressive Overload with Flywheels

The most difficult juggle with loading is how to progressively overload an athlete with isoinertial training. Increasing demands from flywheels are a juggle of three variables: rotational speed, weight, and diameter size. Simply adding more flywheels will not necessarily mean an athlete trains with higher intensity, as concentric forces initiate the momentum and effort drives everything. The amount you can drive down into the platform is the overload you receive. It’s essential that you understand that the size and weight of the flywheel is less important than how you receive the load and how much speed you can put into the machine.

Similar to VBT (velocity based training), flywheels share overlapping concepts of speed and loading, and it’s vital that coaches using isoinertial training know how to manipulate training variables and progress athletes. Four primary variables exist with flywheel overload, and a few sub-variables help shape the details of programming those four.

Inertia Resistance: Force and power are fine summaries of the inertia, and they are calculated by flywheel sensors, such as the kMeter. The assumption that a heavier flywheel disc will create a higher resistance is only partially true. The kMeter solves the quantification of inertia resistance for both coach and athlete.

Contraction Rate: No scientific investigation has drilled down to the F-V curve and how flywheel load and programming create a transfer, but faster eccentric and concentric actions are different than slower movements. Higher velocity contractions may fatigue the faster fiber types, so monitoring training for the quantification of flywheel training is paramount.

Eccentric Reception: How the body receives the load determines how the eccentric overload creates an effect on the body. Just training with a flywheel alone provides a rapid early eccentric overload, but the technique of absorbing the forces dictates how much overload and where you or your athletes receive the stress. It’s easy to visualize two legs pushing up while one leg absorbs the force; it’s harder to visualize an athlete falling with the weight and stopping abruptly at the bottom. Exercise selection and technique are essential in the way eccentric overload stimulates adaptation.

Total Work Performed: Volume, and the distribution of type of work performed, is a factor to how athletes will adapt to, and recover from, flywheels. While there are some theories about the way successive bouts of training will impact later reliance on eccentric load, based on our experience and some research, the body becomes more able to handle strain over time. Distribution of work, meaning how much of it was at higher velocity, should influence the power or strength adaptations of isoinertial training.

Clearly, like the laws and principles of conventional barbell training, there is more to flywheel overload than just slapping another disc on the machine. On the other hand, be confident that you will be able to find better progressive overload approaches than sets and reps alone with experience. More training factors make up progressive overload, but the four variables are enough to be competent with flywheel loading.

Isoinertial Overload Periodization and Programming

Planning a season with flywheels can sound like a big task or something that requires a complex map of training. The reality is that, because flywheel training is a part of the big picture, the amount of changes and adjustments should be only enough to make sure things run smoothly. Over the course of the article, we reviewed that making a few quick additions or changes is not as simple as changing exercise names, but we don’t want you to perceive it as doing brain surgery.

The simplest way to look at planning the season is to think about how much and when you compete and how much you focus on training. With the lines between offseason, preseason, and competitive season blurring more and more, it’s harder to label any phase GPP, SPP, and Competitive. Even if a phase is just a few weeks long, still obey the laws and principles of sports training and plan accordingly. Here are recommendations based on standard training principles and the specific needs that flywheel training require.

GPP: The furthest away from the competition period is sometimes called the offseason, and it’s imperative that most of the gains of eccentric overload are done during this time period. Longer seasons mean shorter preparation times so, on the record, we include isoinertial training with any serious athlete in some fashion in the GPP. During the offseason our volume and flywheel load is at the highest, but speed or revolutions per minute are not maximal like later in the season. Overall, the load of the flywheel isn’t as important as the effort and volume of the athletes using it.

SPP: Typical pre-seasons in team sport are short, so while the phase deserves its own set of guidelines, it’s not very long in most scenarios. Blending qualities in order to transition into competing is the No. 1 approach we see in sports performance, and it’s certainly the case with flywheel training. During this time period, we increase the intensity with the overall training and start slightly decreasing volume. The transition from off-season to competing is tricky, because most of the time we see team coaches and programs make jumps or dramatic changes, thus shocking the system and usually creating DOMS (delayed onset muscle soreness) that athletes hate. We have seen subjective and objective data over the season, and a decrease in late week soreness is significantly lower with the inclusion of flywheels.

CPP: The competitive phase is tricky, as most coaches see it as a time to maintain or allow a decay of capacity, like a detraining leak. Realistically, it’s hard to build a body when opportunities to train are minimal, but clever ways of microdosing intensity and manipulating volume do allow for small gains or preservations of sport power if done properly. We use relatively the same design as the SPP, but drop volume significantly twice. The first half of the season we drop sets by a third, and then drop frequency to once a week on the back half.

To summarize, the pattern of loading is quite simple and very conventional. Speed increases and volume and frequency decrease as the season progresses. The choice to manipulate the loading with flywheels or weight of the inertia is good on paper, but we don’t have enough seasons under our belt to determine if that variable is meaningful.

Experimentation and the Learning Curve

This article is not a blueprint on what do with flywheels, as our own experiences really only include a few exercises used judiciously before graduating to more comprehensive and refined strategies. Collectively, we likely only scratch the surface of what needs to be done in training, and that is the exciting part because there’s room to improve. We hope the article gave you a few immediate ideas of what to think about before you start with flywheel training, but it’s going to be up to your own efforts to fully exploit the benefits of a flywheel system.

Since you’re here…
…we have a small favor to ask. More people are reading SimpliFaster than ever, and each week we bring you compelling content from coaches, sport scientists, and physiotherapists who are devoted to building better athletes. Please take a moment to share the articles on social media, engage the authors with questions and comments below, and link to articles when appropriate if you have a blog or participate on forums of related topics. — SF

 

In our concussion return to play (RTP) protocol, we have reduced premature returns to full activity by capturing and evaluating athlete exertion levels. Our protocol acts as a safety net to catch athletes at Central Michigan University (CMU) who are unable to meet exertional goals or whose symptoms return during the process, preventing them from moving to the next step of the protocol.

The NCAA Injury Surveillance Program showed 1485 concussions sustained by 1410 student-athletes from the 2011-2012 through 2014-2015 academic years. The average annual risk for football athletes is 5.42% while the average number of concussions per football team in a season is 5.63. Of all football teams, 80.6% reported a concussion per football season.

Over the past few years, a variety of organizations have invested a great amount of resources into research to better diagnose, understand, and treat the condition as well as to investigate the long-term effects of concussion and trauma to the brain.

Understanding Concussions: A Priority in Sports

Upon my arrival as Associate Head Athletic Trainer and Head Football Athletic Trainer at CMU, one of my first tasks was to review the Concussion Management Plan. With Dr. Matthew Jackson, CMU’s Medical Director, we identified items we needed to update to the standard medical consensus for concussion management.

At the root of our concern was that concussions were diagnosed primarily with subjective information in the past. This included the patient’s description of their symptoms, mechanism, history, and how they felt. Also, some objective testing measures (SCAT3 and BESS) still involved subjectivity as clinicians complete the ratings. This causes variability and, therefore, creates a minimal delectable change value that we have to take into account.

Dr. Matthew Jackson, Medical Director and Head Team Physician at CMU, states:

“The care of concussions has evolved significantly over the last five years. The heart of the diagnosis process, however, is still dependent on an honest report of the student-athlete symptoms, which is subjective. The name of the game to improve concussion diagnosis and return is the implementation of objectivity. Objective quantitative data is data that can be measured numerically and measured precisely, rather than through interpretation.

With concussions, one of the first objective assessments is the ImPACT neurocognitive testing, using a battery of tests compiling values for memory composite (verbal and visual), visual motor speed composite, reaction time composite, and impulse control composite. The test is also examined on a global cognitive efficiency index, which measures the interaction between accuracy (percentage correct) and speed (reaction time) in seconds on the Symbol Match Test.”

Many assessments and tools have since been developed that eliminate subjectivity and allow objectively diagnosed concussions. “Our department reanalyzed areas of the concussion diagnostic and return process to find areas that were amenable to obtaining objective measurements, the first one identified was balance or postural sway,” Dr. Jackson explains.

At CMU, we have taken steps to objectify our assessment of balance–or postural sway–given that it’s a primary symptom or disability used to diagnose a concussion. We’ve eliminated the BESS test which has some subjectivity with large minimal detectable changes for either inter-rater reliability or intra-rater reliability.

We started using Biodex’s BioSway. The system has a force plate that measures postural sway, or movement of the center of mass from the center point. The force plate and sensors measure this data and provide an output that allows us to have objective data to determine disablement of balance or postural sway, due to concussion, in relation to a baseline value.

John Bonamego, CMU Head Football Coach, states:

“Since my arrival as the head football coach at Central Michigan University, our Sports Medicine Department has undergone consistent changes and improvements. One primary focus of improvement has been the Concussion Management Plan, specifically the return to play process for the student-athletes.

This process is now thorough and extensive to ensure player safety, which is our number one priority as coaches who are responsible for the health and well-being of the student-athletes. When students are recruited to become football players at Central Michigan University, we express to their parents and guardians that their physical and mental health is of the utmost importance, and with this plan and process for the care and progressive return to play, we stand behind our promise.”

Objectivity regarding a patient’s exertional progression has been slower to integrate into the concussion RTP protocols. “One area that I believe is one of the most critical parts of the RTP process is where cardiovascular exertion is meant to identify lingering concussion symptoms that are present before advancing through the protocol and ultimately cleared for sport participation,” Dr. Jackson states.

Two Standard Return to Play Protocols for Concussions

1. One of the first recommendations for RTP protocols came from the Consensus Statement on Concussion in Sport: The 4^th International Conference on Concussion in Sport held in Zurich in 2012.
   • Day 1. Rest: 24 hours asymptomatic
   • Day 2. Light aerobic exercise: <70% MHR
   • Day 3. Sport-specific exercises: running drills, skating drills
   • Day 4: Non-contact training drills: complex drills, passing drills
     Day 5: Full contact practice: after clearance
   • Day 6: Return to play
2. The NFL Head, Neck, and Spine Committee developed this RTP protocol for all the teams under their organization.
   • Day 1. Rest and recovery: return to symptom and neurological baseline
   • Day 2. Light aerobic exercise: stationary bike, treadmill
   • Day 3. Continued aerobic exercise and introduction of strength training: increased cardiovascular exercises and may mimic sport activities, introduce strength training
   • Day 4. Football-specific activities: non-contact football activities
   • Day 5. Full football activity/clearance: after clearance

It has been assumed that an athlete, on day 2, was less than 70% based on verbal instructions to “not break a sweat, pedal at 70%, etc.” On day 3, it has been assumed that causing the athlete to perform a more difficult cardiovascular exercise (i.e.- stair step,elliptical, swim-ex, etc.) would exceed greater than 70% of the max heart rate with similar verbal instructions.

Exertional Testing for Return to Play After a Concussion

To determine an athlete’s true exertion level during the return to play process, we decided to integrate objective measures, if possible. Our first idea was to integrate HR monitors with the athletes. We realized that heart rate would fluctuate so we wouldn’t have a reference output or ability to determine a constant threshold, but it would be a step toward greater objectivity when considering exertion levels for return to play.

Why is it so important to test exertion during the return to play process? Through research efforts, the medical community learned that stressing the human body with exercise stresses the physiologic systems (cardiovascular system, neurological system, respiratory system, muscular system). When a concussion has not resolved, an athlete’s exertional stress to these systems can cause the symptoms to return. There lies the importance of stressing the system to a level that instills confidence that the concussion has resolved enough to move to the next step of the return to play process.

We fear that the lack of objective data to determine exertional levels to the system creates a great limitation where athletes can “cheat the system” and advance to the next step in the protocol when their body and brain are not yet prepared.

“Once symptoms from the concussion have resolved, the student-athlete often wants to get back to sport as fast as possible and sets up the possibility for underreporting symptoms during the exertional component of the return to play protocol,” Dr. Jackson describes.

Underreporting could ultimately cause an athlete to return to competition too early, precipitating the potential for relapse of symptoms, repeat trauma, or a post-concussive syndrome. With objective exertional measurements, we hoped to eliminate the risk of repeat traumas to the brain when it has not recovered.

Objective exertional data can decrease the risk of repeat trauma to an unrecovered brain with an unresolved concussion. Share on X

The HiTrainer gave us the best opportunity to accomplish our goals of integrating objective measures. I was exposed to the HiTrainer when I arrived at CMU through my initial collaboration with Jason Novak, Director of Strength and Conditioning at CMU. Novak brought the equipment to CMU upon his arrival as the Director of Strength and Conditioning and used the equipment in a variety of ways to develop athlete performance.

Novak states, “The implementation of the HiTrainer into our strength and conditioning program has been one of the best additions we have made in my three seasons here at CMU.  It allows us to target specific areas of need on an individual basis. The HiTrainer provides us with the ability to train our athletes at various intensities with quantifiable outputs such as distance, speed thresholds, power outputs, and right/left asymmetry. We no longer have to go by ‘feel’ or just athlete feedback based on of rates of perceived exertion (RPE). We can accurately measure effort, output, and improvement including comparisons of pre- and post-injury.”

Our medical staff was interested initially in the power outputs and right to left asymmetry for uses ranging from post-surgical rehabilitation to neuromuscular feedback processes. “We are now capable of integrating sport-specific conditioning protocols for individual athletes in a controlled environment with specific goals and thresholds that are appropriate for each athlete and their current state of conditioning,” Novak explains.

It’s the threshold training that sparked our use of the system for objective measurement of exertion for concussion return to play. The development of the HiTrainer Concussion RTP step came next.

CMU Sports Medicine Department Concussion Return to Play Protocol

• Day 1. Asymptomatic for 24 hours: rest
• Day 2. Light aerobic exercise: <70% max HR on stationary bike for 30 minutes
• Day 3. Advanced aerobic exercise: between 70-95% on HiTrainer RTP protocol for 30 minutes
• Day 4. Non-contact sport practice and introduction of strength training activities: sport-specific drills and strength training session
• Day 5. Full contact practice after baseline diagnostics: returned to baseline on all assessments, after clearance
• Day 6. Return to competition/games

By using the HiTrainer Pro’s Threshold Training options, we’ve set an exertional standard and have some objective output to ensure that our athletes hit the standard. We accomplish this by having an athlete complete a one-minute max effort walking rep to determine their average speed over the minute timed. We take 70% and 95% of the average speed to determine our upper level threshold and lower level threshold.

These thresholds are displayed on a tablet, which the athlete uses to stay within the thresholds while completing a 30-minute walk on the HiTrainer. Athletes must spend the majority of time within the threshold, without the return of symptoms, to advance to the next day of the RTP protocol.

 

This HiTrainer Concussion RTP protocol constitutes Day 3 of our concussion return to play protocol. We print the report from the HiTrainer RTP and place it in our medical records, aiding in documentation with objective data measures. We believe the use of the HiTrainer lessens the “gap” or “jump” seen from Day 2 to Day 4. Since Day 2 introduces cardiovascular stress to the system and Day 4 is functional activity including stress to all systems, Day 3 has to marry these and meet in the middle to have a truly successful increase in exertional demands placed on the human body.

The HiTrainer accomplishes this better than equipment we’ve used in the past due to the ability to set exertional goals, objectively assess the ability to reach or complete these goals, and create a visual stimulus by having the athlete focus on the tablet displaying the thresholds they must stay within. This causes “now” stress on the neurocognitive system to react and maintain the rest of the body’s systems to reach the exertional goal.

Dr. Jackson admits, “by having a very objective and quantifiable test that more closely simulates sports activity, we can standardize this aspect of the return to play process. The HiTrainer allowed for a very consistent and increase in difficulty for exertional testing that may expose a lingering concussion injury whose symptoms have resolved.”

 

 

 

We’ve used the HiTrainer for over a year, and it has decreased premature returns to full activity; it performs as an objective measurement tool to help us meet exertional expectations and goals in a concussion RTP protocol. “Furthermore the student-athlete consciously or unconsciously is not able to reduce effort in order to avoid symptom onset and at the end of the day allows us to be very confident when the athlete completes the exertional testing using the HiTrainer,” Dr. Jackson explains.

Using athlete exertion levels in concussion protocols reduced premature returns to full activity. Share on X

The HiTrainer Concussion RTP is a safety net, catching athletes who are unable to meet the exertional goals or who have the return of symptoms during the process, eliminating their opportunity to move to the next day of the RTP protocol. Using the HiTrainer as part of our Concussion Management Plan in the RTP protocol, we’ve seen fewer relapses of concussion symptoms later in the RTP protocol or after full clearance for competition.

“The use of the HiTrainer in the concussion return to play also instills confidence in the individual student-athlete that we are doing everything possible to make sure the concussion has truly resolved and that their body is ready to take on the load that occurs in participating in college athletics,” Dr. Jackson states.

From October of 2016 to October of 2017, 28 student-athletes completed the HiTrainer protocol in their return to play process from a concussion at CMU. Of the 28, only three student-athletes had repeat concussions or symptom onset.

• Athlete 1, a collegiate football player, was nine months between concussion diagnoses. Both concussions occurred during in-season contact football–the 2016 and 2017 seasons.
• Athlete 2, also a football player, was only one month between concussion diagnoses in the 2017 season; the medical staff viewed these as two independent concussion events.
• Athlete 3 experienced a return of concussion symptoms fewer than two days after returning from a medically-cleared resolved concussion based on completion of the RTP protocol and return to baseline on all assessments.

It came to light that Athlete 3 was not truthful with his subjective reporting and placed himself at risk; his brain had improved enough to pass the RTP protocol and concussion assessments but not enough to return to participation. This goes to show that, even with technologies to diagnose concussions and stop an athlete with a concussion from returning too early, we still have to rely on athletes reporting their symptoms. Head Coach John Bonamego explains:

“Our Sports Medicine Department has done a great job with integrating technologies to improve the diagnostic and return process of concussion, specifically the step using the HiTrainer to make sure athletes are reaching exertional goals to test their bodies. This gives us great confidence as coaches that when someone returns from a concussion and is cleared to participate by the Sports Medicine Department that they have truly resolved from the concussion and are prepared and safe to take on the stress placed on the body by the game of football.

We here at Central Michigan University do not want a student-athlete back on the field if they are not physically and mentally prepared to return to sport. I believe this process also gives great confidence to the student-athletes who suffer a concussion to definitively know they are ready and capable of return to sport upon the completion of our return to play process.”

Return to Play with Evidence

We’ve made a strong step forward using the HiTrainer in the RTP protocol. However, we have more to do, and it’s exciting that HiTrainer, as a company, shares these beliefs. It is working on developing the system to improve the objectivity of the exertional data, to be 100% individualized to the athlete, and to accommodate factors like fatigue at the end of the protocol.

This constant effort to think outside the box and promote continued advancement in concussion diagnostics and return to play is not only appropriate but also necessary. The company is committed to promoting athletes’ safe return whether from concussions or orthopedic injuries. The HiTrainer is extremely multifaceted and can be used as a performance-enhancing tool as well as a rehabilitation tool.

At CMU, the HiTrainer is a staple in not only the Strength and Conditioning Department but also the Sports Medicine Department. We are fortunate to be one of the few colleges and universities at this time to have access to the equipment and to have entered a partnership for advancement that will aid the health, safety, well-being, and performance of all CMU student-athletes.

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…we have a small favor to ask. More people are reading SimpliFaster than ever, and each week we bring you compelling content from coaches, sport scientists, and physiotherapists who are devoted to building better athletes. Please take a moment to share the articles on social media, engage the authors with questions and comments below, and link to articles when appropriate if you have a blog or participate on forums of related topics. — SF

 

I am often brought into the fold to work with high-performance athletes on improving their running mechanics, whether it is with track & field competitors, professional teams, or elite college athletic programs. Sometimes this takes the form of providing instruction to the coaching or performance staff on the intricacies of sprint form as it relates to their respective sports. Even more often, I find myself teaching private sector strength and conditioning professionals how to work with their athletes—of all ages and abilities—on developing improved mechanics for faster, more powerful running performance.

Integrating Sprint Mechanics into the Fitness Routines of Your General Population Clients

In the private sector cases, facility constraints often limit performance coaches, given that square footage can be very expensive to maintain for a performance training operation. In many cases, private facilities rarely have more than 20 to 25 meters from wall to wall in which to run their sprint sessions. The open area sections reserved for speed and agility work often have a surface of artificial turf or a rubberized floor. However, when linear distance is limited, coaches cannot expect athletes to practically or safely approach their maximum speed capabilities. Thus, I work closely with coaches to devise a strategy for improving acceleration and overall sprint mechanics within the space provided.

Very recently, I spent an intensive two-week period with coaches and trainers at a facility in Lower Manhattan, New York—Drive 495—owned and operated by high-profile fitness trainer and professional, Don Saladino. Drive 495 is a first-class facility in the heart of the SoHo neighborhood in downtown New York City. Don’s at the helm and other exceptional trainers and physical therapists are there, including Charlie Weingroff, Chris Wicus, and Cody Benz. The combination of experienced professionals at the top of their game and a well-outfitted facility make Drive 495 a very attractive destination for big-name actors, fashion models, CEOs, golfers, and athletes. But even the Drive facility has some limitations when it comes to introducing sprinting as a means of training clients.

At the far end of the facility, an open space surfaced with artificial turf provides approximately 18 meters of linear space that is 8 meters wide. The area of the entire gym itself offers almost 50 meters of linear distance, but much of that space is used to provide access to gym equipment, changing rooms, and a therapy room. There is a narrow lane where clients can perform relatively low-velocity sled pushes on a smooth linoleum floor. When the gym is less busy, athletes can do some sprinting along this same strip of floor, exercising caution to avoid collisions with other gym members.

Things got very interesting when I collaborated with Don and Chris to instruct Drive 495 staff on sprint drills and acceleration technique as a professional development in-service. Don also introduced me to a curved-profile, self-powered treadmill known as a TrueForm Runner. Thus, given the space and equipment at my disposal, I was up for the challenge of providing the best possible training model that the staff could integrate with their general population clients. I think the result is a pretty good substitute for an outdoor sprinting workout.

Starting with the Basics: Dealing with Gravity

Regardless of the space at my disposal, I always start beginners with a very basic technical model upon which to build greater complexity, higher intensities, and the changing posture experienced during acceleration and maximum velocity sprinting. I have had exceptional success using the drills developed by Gerard Mach to teach running mechanics, but also building the necessary strength in beginners and injured athletes engaging in return-to-play activities. As people work through marching, skipping, and running drills under appropriate guidance, they develop the musculature and elasticity to provide horizontal propulsion and, more importantly, vertical force production.

It is important to point out that, through my travels, I have found that coaching these drills properly has become a bit of a lost art. I was fortunate to have grown up during the glory days of Gerard Mach’s infusion of coaching mentorship in Canada, being taught the Mach drills at the age of 11 onward. My time spent with Charlie Francis further refined the technique. Coaches that can impart the finer points of the Mach drills to athletes have a distinct advantage over those that do not possess this skill.

The ‘A March’

I love the Mach drills because they provide a very simple means of teaching limb mechanics in a controlled fashion. The marching drills allow you to literally “walk” athletes through the posture and limb movements required for sprinting. The “A March” involves a rehearsal of the vertical qualities of stepping from stride to stride and coordinating arm movements to match the front-side characteristics of the legs. Athletes can maintain maximum hip height by lifting the knee of the swing leg to a point no higher than the height of the hip. As the foot descends downward vertically, it is placed very slightly ahead of the support leg by a few inches. This is the athlete’s first lesson in avoiding over-striding at the expense of hip height.

With general population clients, use of the “A March” is akin to the movements of a Tai Chi martial artist or a classical dancer, both of whom recruit muscles in a manner that advances their movement skill, mobility, and strength. I also use the “A March” to reinforce the pattern of vertical limb travel. While so many athletes are irresponsibly taught to push horizontally on the ground, the “A March” teaches clients to bring the knee to an optimal height and then accelerate the foot downward to a point slightly in front of their center of mass.

There is no need to move quickly during this drill. Clients can progress at a speed that they feel most comfortable with during initial training sessions. At slow speeds, with clients staying on the balls of their feet with slight elevation of the heel off the ground, the “A March” can provide quite challenging work. Muscles are recruited to hold posture while the limbs may move through ranges of motion not typically experienced by your fitness clients.

The ‘A Skip’

While the “A March” introduces postural concepts and limb movement mechanics, the “A Skip” adds limb velocity and elastic response to the exercise. I ask clients to maintain the same posture and limb paths as the marching version, but now accelerate the foot downward to the ground, invoking the stretch reflexes in the foot and lower leg on ground contact. As a result, the client should experience some degree of positive vertical displacement—a concept integral to good sprinting.

You want your clients to vault upward as a result of their downward force on each stride. The intent is to provide light and quick foot contacts, not stomping foot falls. As with the “A March,” the intent of the skipping version is to specifically strengthen the muscles required for sprinting. It is a fantastic means of bridging the gap between the “A March” and the more demanding “A Run.”

The ‘A Run’

The “A Run” provides a more tangible cyclical simulation of actual sprinting. The stride frequency requirements are closer to the four to five strides per second experienced in high-speed sprinting. A good progression when working with fitness clients is to limit knee height during this drill to maintain optimal posture and establish a desirable stride frequency.

Some athletes respond better to a designation of “step-over” height relative to the stance leg. You can designate a lower height “A Run” as ankle step-over height, with calf step-overs qualifying as medium height and opposite knee step-overs designated as maximum height. As the client achieves key milestones (e.g., posture, limb frequency, foot elasticity) at a given “step-over” height, you can advance them to the next level of intensity.

The “A Run” prepares clients for numerous aspects of true sprinting, including stride frequency and vertical force production, but also closely matches the metabolic requirements of sprinting. On average, I try to have athletes produce no less than 30 strides over a 10-meter distance. I tell them that an elite sprinter running 30 strides maximally can take them approximately 65 meters. Performing two sets of 4 x 10m of high speed “A Runs” with easy walks back between reps can be exceptionally demanding, taxing the musculature of the upper body, core, and lower body. They can also do marching, skipping, and running A drills with a resistance band around the hips to reinforce a leading hip position, as demonstrated in Image 2.

Moving Faster: Starts and Accelerations

While the drills can be a good way to introduce sprint mechanics and muscular conditioning, the real thrill comes with accelerating and getting the feel of actual sprinting. When working in a confined space, it is not necessary to run much further than 10 meters for beginners. Teaching the clients how to implement starting technique can cover several sessions alone.

When working in a confined space, it is not necessary to run much further than 10m for beginners, says @DerekMHansen. Share on X

One of the first positions I have beginners do is to start from an extended push-up or plank. I allow them to step forward with one foot, as demonstrated in Image 3, and then have them run off the ground. Fitness clients can do the same, accelerating for a few steps in the initial training session. Once an individual shows proficiency in this start position, I have them start right out of the bottom of a push-up. Sprinting from a prone position off the ground allows clients to attain a reasonable drive angle for their accelerations.

Teaching your clients to implement a relaxed falling start from a semi-crouch position is the next stage in your start training. Encouraging them to rotate forward over the front foot before exploding into the acceleration phase is an energy-efficient means of implementing numerous accelerations. As with all starts, the action begins with a strong lead-arm movement, as demonstrated in Image 4.

A more advanced start technique that helps to build overall starting strength and power is the medicine ball falling start, as demonstrated in Image 5. Similar to the regular falling start, the client rotates over the front foot and then powerfully throws the medicine ball as far as they can, using both feet before initiating the first stride in the acceleration phase.

Maximum Velocity Mechanics: Getting Front Side

While it would be great if you could take all your clients to an outdoor track facility, this is not always possible. In the case of the Drive 495 experiment, we kept our training subjects inside and used a curved-profile manual treadmill to work on maximum velocity mechanics. The problem with conventional treadmills is that they do all the work for you. Put your foot on the front of the treadmill, and the motorized belt sucks your foot backwards—all you have to do is pick it back up and recover it back to the front side of your body again.

Curved-profile manual treadmills are a good option in lieu of an outdoor track facility, says @DerekMHansen. #CurvedTreadmills Share on X

The curved-profile manual treadmills require much greater contribution from the athlete to get the belt moving backwards. As such, the downward vertical force requirements—creating both vertical displacement and horizontal propulsion—are more significant than those required on a conventional motorized treadmill. The Woodway brand of these types of treadmills is very popular, but Don Saladino introduced me to a TrueForm Runner at the Drive 495 facility. The difference was that the Woodway incorporated flywheel technology that helps to keep the belt moving as the athlete creates momentum. The TrueForm Runner treadmill does not have a flywheel, so it requires more contribution from the athlete or client to maintain speed.

Having never run on a TrueForm Runner treadmill, it took me a few sessions of experimentation to find my “sweet spot.” With a few workouts under my belt, I was able to find a groove with my front-side mechanics and attain reasonable maximum velocity mechanics for brief durations. Because the treadmill was not driven by a motor or even a flywheel, I found that I could only maintain high-speed sprinting mechanics for about four to five seconds before my technique suffered. Given this fact, I had to establish optimal work to recovery ratios for my training sessions.

If I wanted to sprint at high speeds, with significant front-side mechanics as demonstrated in Image 7, I could only do four to five second sprints with about 120 seconds of walking in-between bursts. Additionally, I could only put together four to five repetitions before I had to take much longer set breaks. Tempo running at much lower speeds could be done with a more balanced front-side to back-side stride mechanic.

I would perform 30 seconds of running with 30 seconds of walking for four to five repetitions for a total of four to six sets. The TrueForm Runner doesn’t let you relax on the treadmill. Instead, it forces you to maintain relatively sound mechanics at various speeds, and I was noticeably more fatigued than if I did the same workout on a conventional treadmill.

It is worth noting that we tried sprinting on several other treadmills, including the Technogym SkillMill and the Woodway Curve. SpeedFit, Greenjog, XForm, and Assault Fitness also offer curved-profile manual treadmills. It is not yet clear to me which brand of curved, manual treadmill offers the most versatility, but I am encouraged to find an option that can offer the best platform for sprinting, tempo running, and general endurance training, in lieu of a reasonable outdoor training option.

Teaching clients how to run at higher velocities with more-efficient running mechanics needn’t be a difficult task. Use of the Mach drills in a preparatory session, followed by good coaching while on the curved-profile manual treadmill, can be a very effective approach to enhancing the performance of any runner. With the use of simple video technology, you can provide clients with real-time interactive feedback on their running form. It is easy to undertake the biomechanical analysis of stride mechanics and body posture, as illustrated in Image 9, with “before” and “after” screenshots providing clear evidence of positive change.

Leaning for the Finish Line: Making It Work for Your Clients

While we always look for “optimal” training scenarios for our athletes and clients, they are rarely possible. Using sprint drills, short accelerations, and high-speed running on a manual treadmill can prove to be a pretty good alternative to an actual track workout. During the winter months when inclement weather is prevalent, these indoor strategies can help to bridge the gap. Here are some great points that you can pass on to your clients to get them “on board” with a modified sprint-based training program for your facility.

Calorie Burning and Body Composition

There are no fat sprinters out there. Just look at the animal kingdom or watch the Olympics. There is no running for recreation—just running for your life. Survival of the fittest takes precedence. Thus, getting your clients to engage in sprint training can be a very efficient means of improving body composition and general health. The sprint drills themselves can be exceptionally demanding, especially when done properly. Just as stomping on the gas pedal in your car can burn a lot of fuel, sprinting can get your clients to burn calories at a higher rate.

Incorporate elements of the drills into the latter portion of a client’s warm-up. I have always found that doing sprint drills and sprinting prior to weightlifting improved the efficacy of my strength training. The same could be said for your clients.

Recreational Runners and Running Economy

Running at higher velocities requires the body to make use of the elastic properties of all connective tissues. When competitive athletes or recreational runners train these elastic properties, these qualities can make them more efficient runners at slower speeds over longer distances. The top marathoners in the world have exceptional elastic qualities that allow them to run each of the 26 miles in a marathon at a pace of 4 minutes and 40 seconds. In order to achieve such a pace, I anticipate that they are also capable of running under 11 seconds in a 100m race.

For the average recreational runner, working on higher speed qualities through sprint drills and actual sprinting can transfer to their 5km, 10km, marathon, or triathlon performance. Research has also proven this through the use of simple plyometric exercises for long distance running athletes.

General Tissue Health

The “use it or lose it” phenomenon applies in this case. Individuals who do not progressively challenge their muscles and tendons are destined to lose the strength and elasticity that these tissues are inherently meant to demonstrate on a daily basis. While many people can get injuries from over-use conditions, I believe that many others get injured from under-using specific tissues. Just as bone density can suffer from lack of stress and force absorption, tendons and other structures can wither from lack of use. Introducing sprint drills in a progressive manner can be useful in maintaining the quality of these tissues. Even if your clients do not engage in full-out sprinting, the drills can be a good means of maintaining overall tissue health and performance.

Mental Health Benefits

Nothing feels better than moving fast with ease. As we age, we are often discouraged from doing anything deemed too intense or extreme. Sprinting is a test of your suitability to survive and thrive in this life. Given that sprinting is one of the most intense activities that you can perform, being able to sprint on a regular basis appears to be a very good assessment of both your physical health and your mental proficiency, given the extreme neuromuscular demands of such an activity. In a time when chronic stressors dominate the landscape, having periodic exposure to high-intensity acute stressors such as sprinting can have a balancing effect for individuals.

I would like to thank Don Saladino, Chris Wicus, and Thiago Passos of Drive 495 for working closely with me on developing a sustainable model for sprint training with the fitness population. Their insights into making this approach accessible to their clients was invaluable in bridging the gap between elite performers and the general population. I look forward to collaborating more in the future with this group of professionals. Please stay tuned for more high-quality resources on how to implement a sprint-based training program with your fitness clients.

Since you’re here…
…we have a small favor to ask. More people are reading SimpliFaster than ever, and each week we bring you compelling content from coaches, sport scientists, and physiotherapists who are devoted to building better athletes. Please take a moment to share the articles on social media, engage the authors with questions and comments below, and link to articles when appropriate if you have a blog or participate on forums of related topics. — SF

 

Ever since Cal Dietz wrote the book, Triphasic Training, there has been an increased focus on eccentric training for improved sports performance, and a lot of articles about progressions for eccentric training, reducing injury, and improving strength. One component that coaches may overlook is the speed at which athletes perform these eccentric contractions and the role that high-speed eccentric training can play in athlete development.

Much of the eccentric strength work in the past focused on time under tension and slow eccentrics to develop strength or hypertrophy. An example of this type of eccentric training for improving strength is an athlete performing a few sets of supramaximal squats with a four- to six-second eccentric contraction. This is great for improving strength, but at some point, the athlete needs to perform these eccentrics at much higher speeds and faster rates to mimic the forces placed on them when they sprint, cut, or land a jump during athletic competition. Strength coaches need to take these forces into consideration when developing a training program for their athletes.

Understanding the Role of Eccentric Muscle Actions in Sports

During an eccentric muscle action, “…the muscle lengthens because the contractile force is less than the resistive force.” (Haff, page 32) We see eccentric contractions all the time in sports. All field sports include large amounts of acceleration and deceleration within the game. Every time an athlete decelerates, their muscles produce an eccentric contraction.

During a game, an NFL player can hit speeds of 20 miles an hour within 20 yards. When these types of athletes change direction, they are not slowly performing eccentric contractions. These contractions occur with high force and high speed. You can determine one of the factors in an athlete’s speed or explosiveness by how quickly the athlete can absorb eccentric forces and generate a concentric muscle force. This is why prospects perform a three-cone drill every year at the NFL Combine. This test tells scouts the athlete’s change-of-direction ability, as well as their power.

When an athlete can quickly absorb an eccentric force and produce a concentric muscle contraction, they can take advantage of the stretch reflex of the muscle. If a muscle contraction is performed too slowly, the athlete will not be able to benefit from the stretch reflex. Performing variations of squats and deadlifts at slow speeds does not prepare athletes for all of the demands their muscles will experience in a game.

Training for Specificity of Eccentric Muscle Actions

Specificity of training should not only mimic the types of joint angles and movements the athlete will perform during competition, but also the speed of these movements. As coaches, why do we spend so much time trying to strictly develop strength, when we should spend more time doing overloaded eccentric training to better mimic the demands of the sport?

Wirth et al. (2015) conducted a study looking at the effects of eccentric strength training on maximal strength and speed-strength. Participants in the study trained eccentrically using supramaximal loads over a period of six weeks. After six weeks, the strength of the athletes improved greatly; however, vertical jump height showed no significant difference when compared to the control group.

The real benefit to #flywheel training is that the athlete creates the force, says @JFeairheller. Share on X

Let’s look at the equation of power (Power = Force x Velocity) in reference to this study. The force of the athletes improved greatly, and just this alone should have increased their power compared to the control group. The only explanation for production of the same amount of power in the vertical jump as the control group is that the velocity at which they moved had to go down. If strength does not always translate to more power, we should look at alternative training methods to improve both strength and power.

Methods of High-Speed Eccentric Training

What are some of the best ways to increase these eccentric forces during training to emulate the speed of movements during competition? Louie Simmons popularized the use of bands when performing squats. To perform a squat with the band, you must attach the band at the floor or the bottom of the squat rack and then loop it around the bar. This setup will create more force to pull the athlete down into the squat than just with gravity alone. The bands definitely create a higher eccentric force, especially if you accelerate down with the weight, but I’ve found the kBox is the best option for high-speed eccentric resistance training.

 

The kBox uses flywheel technology and inertia to create resistance against the athlete. As an athlete accelerates up from the bottom of a squat, the flywheel speeds up. As the flywheel speeds up, it creates a larger eccentric force during the down phase of the squat. The real benefit to flywheel training is that the athlete creates the force, so you always work the optimal resistance for the athlete.

Inertial Training Improves Strength and Power

At Function and Strength, we completed a nine-week case study to look at the benefits of using high-speed eccentric training via the kBox. During the nine weeks, a highly trained male performed lower body exercises twice a week. The participant used only the kBox as the main component for his lower body days, along with some additional accessory lifts. Once a week the participant performed RDLs on the kBox, and once a week he performed squats on the kBox.

The subject performed all the reps at max effort with a focus on decelerating the flywheel as quickly as possible. We kept the sets and reps the same throughout the nine weeks, with the only change being the number of plates or amount of inertia the athlete used. For the first three weeks, he used two plates with an inertia of 0.050 kgm². For weeks four through six, he used one plate with an inertia of 0.050 kgm² and one with an inertia of 0.025 kgm². Then for the last three week, he only used one plate with an inertia of 0.050 kgm². Before and after the nine weeks, he performed the Go Exxentric 4RM Squat Power test on the kBox using one 0.050 kgm² plate.

We used the kMeter to look at the eccentric peak power, as well as the average force produced. Table 1 shows the pre and post test results, looking at eccentric peak power, average force, 40-yard sprint, vertical jump, and a 1RM hex bar deadlift.

 

Not only did power and speed improve, but strength also showed significant improvement over the nine weeks. Based on these results, the ability to improve eccentric peak power and average force on the kBox yielded a faster 40-yard sprint by .18 seconds (3.6% improvement), a higher vertical jump by 2 inches (8.2% improvement), and a higher 1RM hex bar deadlift by 70 pounds (18.2% improvement). These results are consistent with some other studies performed by Gual et al. (2016), as well as Naczk et al. (2016). Both studies also looked at the effects of inertial training.

Gual et al. (2016) looked at the influence of a weekly bout of inertial squat resistance with eccentric overload on lower limb power. After going through a 24-week study, the results showed a significant improvement in countermovement jump compared to the control group, which did not perform the weekly bouts of inertial squat resistance with eccentric overload. Along with the improvement in jumping ability, both eccentric and concentric squat power showed significantly more improvement versus the control group.

Another study by Naczk et al. (2016) evaluated the strength and power of young active men after performing five weeks of inertial training. Before and after the study, the subjects were scored in countermovement jump, squat jump, maximum force, and maximum power achieved during an ergometer test. Following the five weeks of training, there were significant improvements in muscle force, muscle power, countermovement jump, and squat jump.

When comparing the case study, the Gual study (2016), and the Naczk study (2016) to the Wirth study (2015), there is one key difference. That difference is the speed at which the participants performed the eccentric portion of the exercise. All of the studies showed improvements in strength. However, when overloading the eccentric portion of the lift with higher speeds, we see a much better translation to power when compared to performing eccentrics slowly. This makes sense when looking at the dynamic movements of athletes because these types of exercises do a better job simulating the speed of movements during game play.

If you want to move fast, you have to train fast, says @JFeairheller. Share on X

When a basketball player prepares to jump for a block or a rebound, they do not slowly lower themselves and then try to jump as high as they can. They lower themselves quickly and then jump up quickly. Training with high-speed eccentrics does a much better job of copying this movement speed. If you want to move fast, you have to train fast. Cal Dietz said “every dynamic movement begins with an eccentric muscle action.” (Dietz, page 83) The less time an athlete can spend in the eccentric portion of the movement, the more dynamic and powerful the countermovement becomes.

Shifting Toward a Better Training Model for Athletes

As strength coaches, we may have only a few months to train an athlete during the offseason. With this limited training time, it’s crucial to be as efficient with our programming as possible in order to see the best results with our athletes. Training with supramaximal eccentrics is great for someone looking to specifically improve strength. For athletes looking to improve power, change of direction, cutting, and jumping ability—along with strength—a good option is high-speed eccentric training.

Since you’re here…
…we have a small favor to ask. More people are reading SimpliFaster than ever, and each week we bring you compelling content from coaches, sport scientists, and physiotherapists who are devoted to building better athletes. Please take a moment to share the articles on social media, engage the authors with questions and comments below, and link to articles when appropriate if you have a blog or participate on forums of related topics. — SF

 

References

• Dietz, Cal, and Ben Peterson. Triphasic Training. 2012. Hudson, WI: Bye Dietz Sports Enterprise. Page 83.
• Haff, G. Gregory, and N. Travis Triplett. Essentials of Strength Training and Conditioning, 4th Edition. 2016. Champaign, IL: Human Kinetics. Page 32.
• Gual, Gabriel, Azahara Fort-Vanmeerhaeghe, Daniel Romero-Rodriguez, and Per A. Tesch. “Effects of In-Season Inertial Resistance Training With Eccentric Overload in a Sport Population at Risk for Patellar Tendinopathy.” Journal of Strength and Conditioning Research 30(7) (2016): 1834-1842. doi: 10.1519/JSC.0000000000001286Naczk, Mariusz, Alicja Naczk, Wioletta Brzenczek-Owczarzak, Jaroslaw Arlet, and Zdzislaw Adach. “Impact of Inertial Training on Strength and Power Performance in Young Active Men.” Journal of Strength and Conditioning Research 30(8) (2016): 2107-2113. doi: 10.1519/JSC.0b013e3182a993c2
• Wirth, Klaus, Michael Keiner, Elena Szilvas, Hagen Hartmann, and Andre Sander. “Effects of Eccentric Strength Training on Different Maximal Strength and Speed-Strength Parameters of the Lower Extremity.” Journal of Strength and Conditioning Research 29(7) (2015): 1837-1845. doi: 0.1519/JSC.0000000000000528.

We live in a very progressive and ground-breaking time in the field of sports performance. Everybody wants to be the best strength and conditioning coach, physical preparation specialist, technological guru, and what have you. They want to show they are pioneers in the industry by manifesting brand-new training methodologies through research, innovative exercises, technological advancements, and advanced programming strategies. There’s one problem, though. What happened to good ol’ coaching?

New multifaceted information in our field is prodigious. Yet, the best coaches in the world take complicated matters and simplify them so that everybody can understand and apply them. If you got into this industry to try and reinvent the wheel for your own intents and purposes, you are misguided. As coaches, it is our responsibility to put our own schema aside for the betterment of our athletes. In our gym, I believe we have revolutionized the way we train team sport athletes by implementing the latest research, promoting individuality within a team setting, managing many personalities, and creating a culture that fosters athletes who are hungry, humble, and committed to excellence.

Creating Individuality Within a Team Training Session

I know I have 60 to 75 minutes to work with a team consisting of 16-18 basketball players. Their head coach just ran a two-hour open gym, three athletes have a knee injury, two of them have a shoulder injury, and they all have a game in four hours. I would be doing the players and the coach a disservice if I put together a bunch of exercises that were not individualized to each athlete’s needs, just for the sake of “getting the work done” or to “look cool” for an Instagram video.

How do I manage a full 18-man roster where each player has individual needs? Easy—preparation. We train team sport athletes three times per week and operate in four 12-week macrocycles: pre-season, in-season, post-season, and off-season. We structure each block as follows:

A two-week assessment/acclimation period. We test our athletes in week 3. Weeks 4-10 consists of progressive training. Week 11 is a low-stress week, priming our athletes for week 12, which is testing week.

Figure 1 shows our four 12-week macrocycles for basketball teams that we have established within each phase of the year. The training template remains the same, but we manage the exercises, intensity, and volume according to the external stresses on our athletes. As mentioned previously, I know each athlete, their needs, and their injuries based on the two-week screening period prior to our actual training, regardless of what phase of the year it is. Every athlete will be in a different stage depending on where in the year they are in their season. Each athlete has specific pre-work they must perform prior to our session. We break them into their groups based on their neural ability, anthropometrics, fitness, and strength.

The program remains the same, with slight variations in exercises based on the aforesaid reasons. We always work backwards with the end goal in mind. A key part of our job is to be in constant communication with the coach so we know what external stressors athletes experience. This allows us to scale the training up or down based on the way they are feeling.

Figure 2 shows how we allocate our time for each facet of training. We train multiple teams a week and we have found what works best for most team sport athletes regarding the intensity, duration, and frequency of each sequential training component. A guideline or template is necessary to ensure we leave no stone unturned in their physical preparation process within that seasonal microcycle. We have found that training three times a week in a 12-week off-season block broken down into a force-dominant lower, heavy upper, and velocity/dynamic lower (top speed, change of direction, throws) based days elicits the best results from microcycle to microcycle.

Our time frames are always based on the attention span, work capacity, and ability to comprehend the movements of each team we work with. For example, we have found that high school females have longer attention spans than high school males. We can spend more time teaching higher brain activities like sprinting, jumping, and throwing with high school females versus high school males. In turn, the benefits are mutually inclusive. We teach females who have more trouble generating intent and effort for longer of periods of time. Therefore, they spend more time practicing and getting better at what they are less efficient in.

Figure 3 shows two sessions of the three times weekly 12-week pre-season basketball training block. We found that four-week mini microcycles within each 12-week block deliver the best results for our athletes. The learning curve for each concept takes slightly longer, and the adaptation to specific stressors is generally longer as well.

The above figure represents a template that each athlete follows, but we make changes accordingly based on individual needs, anthropometrics, and injury limitations. You can see that we leave a lot of room for personal notes on each athlete, including the technicality of a movement, ability to comprehend, and metrics. If time does not permit, we cut some things out and the more important things take precedent.

The measure of an athlete is how they react to something that doesn’t go their way. Share on X

One unique aspect of our programming that we never neglect is team competitions. This is a high-priority training component included for every team we train. Team competitions are sport-specific and challenging, and they reveal your team leaders. The measure of your athletes is how they react to something that doesn’t go their way. Sports are competitive and we try to mirror that competitiveness every week within our training cycles and the guidelines of our programming.

Coaching and Managing Your Athletes’ Personalities

As coaches, we wear many masks. It is our responsibility to prepare our athletes, not only physically, but mentally as well. We are put in unique positions that allow us to demand respect, honesty, and above all, trust. What makes a great coach? It’s the ability to lead—to make things happen, maximize resources, and inspire. It’s the extraordinary quality that solves problems and helps the athlete come to a new level of understanding what is possible. It’s the skill and talent to influence and guide our athletes to make real breakthroughs and create lasting change.

Great coaches have vision. They understand where their athletes are mentally and physically. Coaching extends well beyond directing activity. A team of 15 athletes is a team of 15 individuals, each with a different upbringing, temperament, and external influences, all brought together for one common goal.

How you communicate with your athletes is just as important as how you program for them. Your persona and the way you carry yourself as a coach are paramount. Fifty-five percent is your body language, 38% is your tonality, and 7% is what you actually say. Do you stand tall, dress well, and shake your athlete’s hand when you see them? Or are you discombobulated, carry yourself poorly, and don’t address your athletes firmly? These subtle things make a big difference in getting new/old athletes to respect you and “buy into” your beliefs.

There are three types of tonalities with which you address your athletes. Unbeknownst to you, your athletes subconsciously pick up on the messages you unwittingly send them. When you seek rapport, it implies you are trying to overtly seek the approval of your athletes. Consequently, you put the ball in their court. As a result, their impression of you is belittled, regardless of your knowledge. Breaking rapport implies you are talking down to your athletes. If you train a team of 18 high school girls and communicate with them in a condescending way, they will instinctively be reluctant to trust you. Know your audience. Neutral rapport implies commonality. You both respect one another. You respect each other’s opinions and are more receptive to feedback.

Verbal content is the last impression you make on your athletes. They do not care about the “science” or the “why” behind your programming. They care about how you make them feel. When you instill confidence, work ethic, and leadership in your athletes, the ramifications will go far beyond the physical improvements they make in the gym.

Remember, we have the end game in mind with our athletes. When I explain a series of exercises and an athlete responds, “Ugh, these are the worst,” I’ll say, “Is that how a leader would respond?”. Taking an athlete aside and simply telling them how well they did today will mutually benefit both parties.

The only way to hone your craft as a coach is to spend quality time in the trenches. Share on X

Athletes gauge your ability as a coach on how you carry yourself, how relatable you are, and how you make them feel. Experience is the ultimate teacher. I have spent more than 5,000 hours on the gym floor in the last two years, programming, training, and developing amazing young athletes. I have learned that the only way to hone your craft as a coach is to spend quality time in the trenches. You must have the ability to bring these individuals together, bring out the best in one another, and create a culture that has a lasting impact.

Creating an Unmatched Culture

At the gym, we have an unwritten rule. If you are late—meaning, if training starts at 3:00 p.m. and you stroll in at 3:01 p.m.—you must perform one of the following: 50 calories on the AirFit, 500m on the Ski, or 500m on the Row. This is not a punishment; it’s a teaching tool. We want our athletes to be accountable for themselves, not for us.

In college and the pros, nobody cares about how you “feel.” They care about results. Results are predicated on habits that athletes can learn. They do all of their specific pre-work on their own 10 minutes, prior to the session. We explain the exercises the first week. They must take it upon themselves to get the work done prior to our session start time in the following weeks.

We always have two to three coaches on each team. Every coach must have a notebook with a log of all the names of each athlete in their group. This log includes the intensity used for each exercise and the strengths and weaknesses of each athlete. We address every athlete by name, which we know prior to our first session when working with any team. The details matter.

We always ask the athletes about their day, their weekend, and even check in on their families. Establishing a relationship with our athletes is paramount, and here’s the secret: You actually have to care. I train over 100 athletes a week, and I go to every athlete’s games. I know them by first and last name; I know their families; I know what music they like, what movies they enjoy, and sometimes who they’re dating.

Remember, in the private sector, these athletes DO NOT have to train with you. There are many gyms that “train athletes” near yours. What makes your facility unique?

One of my favorite quotes is from Peter Drucker: “Culture eats strategy for breakfast.”

When you build a culture that fosters athletes who are hungry, humble, and committed to excellence, the rest of the components fall into place. Building a culture starts with the foundation. Coaches are the foundation on which everything inside our four walls is built.

Building a culture starts with the foundation, and coaches are that foundation. Share on X

We hold ourselves accountable every day by living the code, caring about our athletes, and meeting regularly to improve our programming for our athletes. We regularly highlight our athletes on social media, put up posters in the gym, and create training montages dedicated to them. Furthermore, we always have an athlete of the week. This is a subtle way to spotlight what happens in the gym and give recognition to athletes who may not always be rewarded for their hard efforts.

While Science Is Important, Don’t Forget About the Craft

Coaching is an art. We cannot get get distracted by our own agendas in our industry. We must remember that it is the athletes who provide us with jobs. We owe it to them to provide them with the best hour of their day, over-deliver with service, and always ensure they are getting better. Own the foundation. Create a culture in your gym that fosters athletes who are hungry, humble, and committed to excellence, and watch the results as your athletes reach new heights.

Since you’re here…
…we have a small favor to ask. More people are reading SimpliFaster than ever, and each week we bring you compelling content from coaches, sport scientists, and physiotherapists who are devoted to building better athletes. Please take a moment to share the articles on social media, engage the authors with questions and comments below, and link to articles when appropriate if you have a blog or participate on forums of related topics. — SF

By Jennifer Reiner-Marcello, Brandon Marcello

In the world of rehabilitation and training, eccentric exercises are imperative for developing strength, power, and resilience (Alfredson, 2003; Gonzalo-Skok et al., 2016; LaStayo et al., 2003; Roig, Shadgan, & Reid, 2008). Traditionally, eccentric movements are trained using barbells, dumbbells, tubing, chains, and plyometric exercises. The presence of flywheel technology (e.g., VersaPulley™, kBox, Desmotec, Proinertial) for training spans several decades in both the rehabilitation and performance community. However, not until recently has this form of inertia-based training received more attention from the collegiate, private, and professional training centers.

Perhaps this new-found interest is due to the simplicity of training multidirectional movements in the horizontal and vertical planes in an eccentrically overloaded environment. This is possibly the most effective way for increasing muscle strength (Brandenburg & Docherty, 2002; Hedayatpour & Falla, 2015; Hortobagyi, Barrier, & Beard, 1996; Hortobagyi et al., 1996; Hortobagyi, Devita, Money, & Barrier, 2001; B. Johnson, 1972) in a shorter period of time when compared to more traditional 1:1 (concentric:eccentric) exercise training(English, Loehr, Lee, & Smith, 2014).

It’s this eccentric overload applied in a task-specific environment that captures the next level of improved performance otherwise unattainable through traditional training methods.

Flywheel Training: A Long History in Science and Practice

Research on flywheel devices dates back to the early 1900’s by Krogh 1913, Hill 1920, and Hansen and Lindhard in 1923 (Hansen & Lindhard, 1923; Hill, 1920; Krogh, 1913), but the use of flywheels for performance became popular in the late 1980s and early 1990s when NASA began examining ways to maintain lean muscle mass and bone density during extended travel in the zero-gravity atmosphere of space (Dudley, Tesch, Miller, & Buchanan, 1991). Since then, numerous studies have been published demonstrating the effectiveness of flywheel training for developing strength, hypertrophy, power, injury prevention, and rehabilitation (Alfredson, 2003; Gonzalo-Skok et al., 2016; LaStayo et al., 2003; Roig et al., 2008).

The benefits of inertial based training are rooted in the extensive research surrounding eccentric training. Beginning at the cellular level, forces imparted to tendons and muscles are converted from mechanical stimuli into biochemical signals. This is referred to as mechanotransduction (Maffulli & Longo, 2008), which in turn results in remodeling of the myofilaments and adaptation of the viscoelastic properties of the muscle (Yu, Furst, & Thornell, 2003).

Research shows these other benefits also occur:

• recruitment of slow-contraction motor units
• activation of a large number of motor units (neural adaptation)
• increased dynamic and passive muscular endurance (mechanical adaptation)
• longitudinal addition of sarcomeres
• adaptation to the inflammatory response
• adaptation to maintain muscle excitation-contraction coupling (cellular adaptation) (McHugh, 2003; Miyama & Nosaka, 2007).

These positive cellular, mechanical, and neural adaptations are the result of the repeated bout effect (RBE). Consequently, there is an increased “stiffness” of the muscle-tendon unit (Lindstedt, LaStayo, & Reich, 2001) that makes the tissue more resilient and able to handle higher loads or forces imparted into the structure.

While it would seem that an increase in passive muscle stiffness would limit joint range of motion, evidence leads us to believe the contrary. In fact, according to a systematic review by O’Sullivan in 2012, long-term eccentric training revealed improved flexibility (O’Sullivan, McAuliffe, & Deburca, 2012). This improvement is attributed to an increase in the number of sarcomeres distributed in series, also known as sarcomerogenesis (Butterfield, Leonard, & Herzog, 2005; Lynn, Talbot, & Morgan, 1998; Yu et al., 2003).

It’s proposed that sarcomerogenesis, along with adaptations to the passive elements within the muscle, create a shift in the muscle length-tension curve that consistently occurs with eccentric training (O’Sullivan et al., 2012). The resulting benefit includes greater motor control throughout a larger range of motion ultimately leading to improved performance and protection against injury.

Building High Total Body Resilience with Eccentric Overload 

Eccentric training’s protective benefits have direct implications in rehabilitation and reconditioning. Because forces are extremely high during the eccentric, or lengthening phase, of movement, injuries often occur during the deceleration (LaStayo et al., 2003) of the body. If the forces needed for deceleration exceed those of the muscle-tendon system, injury to the muscle, myotendinous unit, the tendon itself, and the osteotendinous insertion may occur (LaStayo et al., 2003).

Research suggests that athletes with a history of recurring hamstring and adductor muscle strains possess greater impairment of their eccentric strength (2-fold) as compared to concentric strength, suggesting that improvement in the former may minimize the risk of injury (LaStayo et al., 2003). At the knee, the hamstring’s eccentric activity provides a posterior pull on the tibia to offset the anterior force of the quadriceps (Shimokochi & Shultz, 2008).

Along with their role in knee stabilization, the hamstrings are eccentrically activated before initial limb contact in movements such as cutting, stopping, and landing maneuvers (Nyland, Shapiro, Caborn, Nitz, & Malone, 1997). This “presetting” of the hamstrings along with eccentric quadriceps activity during the loading phase is crucial for proper shock absorption and protection against knee injuries such as ACL tears.

Similarly, training eccentrically for deceleration forces encountered in the upper extremity is pertinent for rehabilitation and injury prevention of the overhead athlete. The distraction forces from throwing a baseball at the glenohumeral joint are equal to one to one and a half times body weight (Fleisig, Andrews, Dillman, & Escamilla, 1995). For this reason, muscles in the shoulder must undergo high decelerative eccentric contractions to preserve healthy joint arthrokinematics (Ellenbecker, Davies, & Rowinski, 1988). Whether used along the rehabilitation continuum or as part of a training program, eccentric and eccentric overload training are critical to preparing the athlete for the forces they will encounter during practice or competition.

Eccentric Overload: Performance

As we turn our focus to performance, we must ask what the benefits are to strength, power, hypertrophy, and injury prevention when adding eccentric overload training. What does the science indicate? The higher forces generated (2-3 times greater than those produced either isometrically or concentrically) (Johnson, 1972; Jones & Rutherford, 1987) through eccentric training have shown it to be a superior method in developing both strength and hypertrophy (Hollander et al., 2007).

#EccentricOverload is a superior method to develop strength and hypertrophy. Share on X

Because it’s more effective than concentric training at increasing total and eccentric strength (Roig et al., 2009), it should be used to enhance the effects of the typical training seen in most weight rooms around the world. Studies have also shown that eccentric overload training is superior to eccentric underload in its ability to stimulate increases in strength (English et al., 2014), but even more significant is the speed in which training adaptations take place. When compared to traditional concentric/eccentric training, eccentric overload was the only training regimen to increase lower body lean muscle mass and show improvement in bone mineral density after only eight weeks of similar training (English et al., 2014).

Eccentric Overload Training: Hypertrophy 

Further studies examining eccentric overload training and its effects on muscle hypertrophy showed similar effects (de Souza-Teixeira & de Paz, 2012; Hedayatpour & Falla, 2015; Mayhew, Rothstein, Finucane, & Lamb, 1995; Ojasto & Hakkinen, 2009; Tesch, Ekberg, Lindquist, & Trieschmann, 2004; Vikne et al., 2006; Walker et al., 2016).

Greater hypertrophy was also reported following chronic resistance training comprised of coupled eccentric and concentric actions or eccentric actions compared with concentric actions only (Hather, Tesch, Buchanan, & Dudley, 1991; Higbie, Cureton, Warren, & Prior, 1996; Hortobagyi et al., 1995; Norrbrand, Pozzo, & Tesch, 2010) This is another reason why using eccentric overload training in conjunction with traditional weight training should be heavily considered.

Put simply, greater muscle hypertrophy is a result of enhanced muscle protein synthesis, which is a product of higher mechanical loading of the muscle. This type of mechanical loading is created by eccentric muscle actions (Norrbrand et al., 2010).

From the vantage points of power development and application of force, higher muscle forces can be produced during eccentric contractions compared with concentric (Roig et al., 2009). And while all types of training can improve power in multiple planes of movement, the specificity of training adaptation principle mainly prevails (Gonzalo-Skok et al., 2016).

One particular study examined this specificity by programming exercises in both the vertical and horizontal planes. The results were what one would likely expect. Those who trained vertically improved in all planes, but made the most gains vertically (vertical jump) and those who trained multi-directionally also improved across the board but gained the most multi-directionally (acceleration and change of direction) (Gonzalo-Skok et al., 2016).

Research from 2016 indicated that those who train using eccentric overload were able to produce a significantly greater breaking and propulsive contact time (de Hoyo et al., 2016). This suggests that eccentric overload could be a fundamentally important mechanism underpinning change of direction ability (de Hoyo et al., 2016).

In short, neuromuscular and functional changes induced by exercise are specific to the mode of exercise performed (Hedayatpour & Falla, 2015). Therefore, by not performing exercises that encompass eccentric overload as a stimulus, an entire cascade of neural, physiological, and muscular adaptations will be neglected and underdeveloped. While all of these methods are important to the training, rehabilitation, and reconditioning of athletes, they offer mostly constant concentric and eccentric load in exercises emphasizing vertical actions.

In most sports, athletes are required to repeatedly perform short explosive efforts such as accelerations and decelerations during changes of direction (de Hoyo et al., 2015). The capacity to dissipate the forces during abrupt deceleration (breaking ability) is critical to injury prevention, while the ability to decelerate and reaccelerate in a short period of time (reactive strength) is paramount to enhanced performance.

Whether one is training to improve strength, power, or change of direction, rehabilitating from an injury, or improving resilience, the flywheel designed by VersaPulley™ is a safe and effective tool for training at any load, at any speed, and in any plane within an infinite amount of exercise variation. Because of its high/low capabilities, the VersaPulley™ allows for the prescription of exercises in all planes of motion, creating training stimuli from the general to the specific.

Implementation of eccentric overload strength training has been lacking in traditional strength and conditioning program designs (Hollander et al., 2007). In short, if programmed and implemented correctly, eccentric overload training should be an integral part of any comprehensive rehabilitation or training program seeking to improve performance and decrease injury potential.

Going Beyond Gravity with Flywheel Eccentric Training

In conclusion, traditional weight training using gravity-dependent tools leaves a gap in preparing an athlete to manage all aspects of performance. Barbells, dumbbells, kettlebells, and the like offer constant concentric and eccentric load in exercises emphasizing vertical action, yet they rarely encompass horizontal/lateral actions offering eccentric overload (Tous-Fajardo, Gonzalo-Skok, Arjol-Serrano, & Tesch, 2016). Furthermore, a person’s ability to complete an eccentric-isometric-concentric cycle under maximal load is limited by the force production in the concentric phase (Hortobagyi, Devita, Money, & Barrier, 2001).

This means that traditional weight training creates an ideal environment for concentric strength and eccentric underload. Even with the addition of tools such as bands and chains, an eccentric overload is not achieved, and attempting to do so in this setting would be unsafe and expose those training to an unnecessary risk of injury. While we have used a number of flywheel devices, we have the most familiarity with the VersaPulley™ which was designed to create those moments of eccentric overload, allowing the athlete to be exposed to these stresses in a non-impact, concentrically-driven, and eccentrically overloaded environment. The flywheel device picks up where traditional gravity-based weights, chains, bands, and air-powered machines stop.

Since you’re here…
…we have a small favor to ask. More people are reading SimpliFaster than ever, and each week we bring you compelling content from coaches, sport scientists, and physiotherapists who are devoted to building better athletes. Please take a moment to share the articles on social media, engage the authors with questions and comments below, and link to articles when appropriate if you have a blog or participate on forums of related topics. — SF

References

• Alfredson, H. (2003). Chronic midportion achilles tendinopathy: An update on research and treatment. Clinics in Sports Medicine, 22(4), 727-741.
• Brandenburg, J. P., & Docherty, D. (2002). The effects of accentuated eccentric loading on strength, muscle hypertrophy, and neural adaptations in trained individuals. Journal of Strength and Conditioning Research, 16(1), 25-32.
• Butterfield, T. A., Leonard, T. R., & Herzog, W. (2005). Differential serial sarcomere number adaptations in knee extensor muscles of rats is contraction type dependent. Journal of Applied Physiology (Bethesda, Md.: 1985), 99(4), 1352-1358. doi:00481.2005 [pii]
• de Hoyo, M., Sanudo, B., Carrasco, L., Mateo-Cortes, J., Dominguez-Cobo, S., Fernandes, O.,… Gonzalo-Skok, O. (2016). Effects of 10-week eccentric overload training on kinetic parameters during change of direction in football players. Journal of Sports Sciences, 34(14), 1380-1387. doi:10.1080/02640414.2016.1157624 [doi]
• de Hoyo, M., de la Torre, A., Pradas, F., Sanudo, B., Carrasco, L., Mateo-Cortes, J.,… Gonzalo-Skok, O. (2015). Effects of eccentric overload bout on change of direction and performance in soccer players. International Journal of Sports Medicine, 36(4), 308-314. doi:10.1055/s-0034-1395521 [doi]
• de Souza-Teixeira, F., & de Paz, J. A. (2012). Eccentric resistance training and muscle hypertrophy. Sports Medicine and Doping Studies, S1(004)
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