Daniel Kadlec is currently the Head Strength & Conditioning Coach for Softball Western Australia. He is also Head S&C Coach for Claremont WFC in collaboration with Edith Cowan University, while completing a Ph.D. in sports science sponsored by VALD Performance. He previously served as an S&C coach in a private facility (PlusD Sports) in Solingen, Germany, for seven years. He has worked with various teams, including professional handball, Germany Women’s Rugby 7s, and the centralized women’s Judo athletes.
Freelap USA: What are some key components of building linear sprint speed in the context of team sport athletes?
Daniel Kadlec: If you want to get faster and invest your time and energy as efficiently as possible, you need to expose yourself to maximum velocities on a regular basis…and just sprint. With that, I refer to a max effort activity over at least 30 meters and, if done over several sets, there needs to be sufficient rest between the single reps. This might sound like common sense, but if you neglect one of these aspects, your athletes most likely won’t get faster and you’ll just be wasting their time and energy.
We know from biomechanical research that joint kinetics and the associated muscle force outputs increase exponentially as we move from jogging to running to sprinting. As we approach maximum velocities, we rely more and more on the muscular performance of the hip flexors, hip extensors, and knee flexors, whereas knee extensors and plantar flexors don’t change much. As their function is more likely to be modulating stiffness than actively contributing to propulsion, we keep those joints relatively straight during ground contact. In order to get team sport athletes to sprint at 100% there needs to be competition. It’s rare to see someone sprint at 100% on their own, but against someone else—they’ll compete.It’s rare to see an athlete sprint at 100% on their own, but against someone else—they’ll compete, says @DanielKadlec. Click To Tweet
We know that maximum velocities are needed to get faster, but I still often hear that this occurs at around 50-60 meters, as it does with 100m sprinters. However, in team sports, maximum velocity is likely to be reached much earlier. It has been demonstrated that field sport athletes need about 20 meters to reach maximum velocity from a static start and then we need some extra distance to get that exposure in. From a practical standpoint, almost all athletes will already start to decelerate before they reach that set distance, so I just lie to them and set the cones about 10% further than what I want them to sprint.
In order to reach maximum velocities across several reps, you need to have enough rest in between. The general rule of needing one minute of rest per every 10 meters of max effort sprinting still holds true. Also, as long as they’re breathing heavily, they’re not ready yet. And this can be another challenging part, as most team sport athletes are just not used to doing nothing and having a rest. Therefore, I like to distract them during the rest period by prescribing low-intensity activities like neck or rotator cuff exercises and balance and/or hand-eye coordination drills. However, I’d much rather have them sit down, breathe, and do nothing.
I think we all agree that hitting proper mechanics during sprinting is essential to be as efficient as possible. However, teaching someone to attain optimal mechanics can be quite challenging and frustrating. I relied for a long time on traditional running drills, such as wall drills, A-skips, B-skips, straight leg bounds, etc., with the common external instructions about toe and knee position and their posture. But what I’ve seen over and over again is athletes who could pretty decently execute these drills but still couldn’t sprint, and vice versa.
So, I started to question that: How does one skill transfer to another? And therefore, I almost completely ditched all those drills. One method I prefer to use now is wickets, which subconsciously forces the athlete to adapt more advantageous mechanics. However, it’s not guaranteed that each athlete will benefit from it right away. Usually, they are a bit slower over wickets, as they have to use certain structures or patterns that they haven’t before. So, it can be seen as a “special strength exercise” that takes time and can end in chaos every now and then.
Freelap USA: In the same vein, what are some important ideas in building agility and reactivity for the team sport population?
Daniel Kadlec: Right now, I’m quite reserved and skeptical about whether we, as S&C/physical preparation coaches, can actually improve agility within our practice—but we surely have a meaningful impact with our work to support this essential athletic ability. My biggest concern is that we underestimate the inherent complexity and specificity of not just the perceptual-cognitive, but also the emotional and behavioral demands during in-game scenarios, which therefore limits the transfer of whatever agility drill we do during our practice. However, I’m happy to be proven wrong.
We know that, by definition, agility is dependent on the visual-cognitive and the motor execution. Or, in other words, what one is able to perceive and do through movement. Elite athletes have been shown to be superior to sub-elite athletes in sport-specific tasks, including visual cue utilization, pattern recall and recognition, visual search strategies, and knowledge of situational probabilities. These abilities are tightly related to superior anticipation and decision-making and are used interchangeably with the ability to “read the game.”
Also, during the performance of “open” skills such as cutting and evading in perceptually demanding situations, visual-perceptual skill and decision-making abilities seem to act as the limiting factors to performance rather than movement production—i.e., your linear and multidirectional speed capacities. Based on that, improving their decision-making abilities should benefit our athletes, right? So how can we do that?
I often see very creative and impressive agility drills on social media channels, where one or more athletes has to respond to another athlete or athletes in an offensive or defensive task. Without a doubt, there is an element of decision-making and anticipation; however, I want to highlight the impact that emotion and behavior have on perception, and therefore action in high stakes competition. With this inherent difference, your agility drills would need to also incorporate those cognitive, emotional, and behavioral demands of competition—which I feel is very hard to achieve.
Further, I argue that elite athletes have just accumulated more hours in sport-specific/deliberate practice compared to sub-elite athlete. Moreover, elite athletes most likely spend more time in activities that entail the appropriate complexity and specificity in order to develop sport- and even position-specific perceptual-cognitive skills (e.g., video training, organized team practice, individual instruction with a coach and competition). So, what can we do?There are large limitations on most drills we can design to facilitate an athlete’s decision-making and anticipation abilities. These abilities need years and years to develop, says @DanielKadlec. Click To Tweet
From my point of view, there are still large limitations to most drills we can design to facilitate the decision-making and anticipation abilities, so be realistic in what you can achieve as an S&C/physical preparation coach. These abilities need years and years to develop. There is a reason why the term “experienced athlete” is usually allocated to athletes who “read the game” exceptionally well, and why Chinese athletes (in select sports) dominate the competition—they have experienced a greater volume of sport-specific competition, and there are few-to-no methods to fast track that. With my work increasing physical capacity and preparing for worst-case scenarios, I can give athletes the opportunity to experience greater quantities and qualities of deliberate practice. That’s how I understand my role.
Freelap USA: What have you found with the use of overcoming isometric work and its acute impact on athlete KPIs?
Daniel Kadlec: In my experience, acute improvements via a post-activation potentiation (PAP) effect in selected (speed/power) KPIs can be done in numerous ways, whereby overcoming isometrics are surely an appropriate and effective option. With that said, I see any modality or activity appropriate that stimulates the neural system, preferably in KPI/movement-specific ranges, while eliciting as little fatigue as possible. And this should be part of any well-structured warm-up prior to a maximal output anyway.
Universities and research groups are to blame for many coaches thinking PAP can be some sort of game-changer. The current overemphasis on PAP research is due to its relative ease in terms of study design and amount of time spent per participant. Also, the often-argued potentially superior chronic adaptation with a PAP method compared to a non-PAP training approach is yet to be proven, and a study—from a methodological point of view—is hard to conduct.The current overemphasis on PAP research is due to its relative ease in terms of study design and amount of time spent per participant, says @DanielKadlec. Click To Tweet
Nevertheless, one part of my current Ph.D. study is on the chronic effect of overcoming isometrics and its influence on athletic performance, as this is anecdotally a frequently used method. However, evidence is lacking, especially from an applied setting. Based on my pilot study, a four-week isometric intervention training program (2 sessions/week, 8×3 of 3-second max effort isometric mid-thigh pull with 10-second intraset and 3-minute interset rest periods) elicits meaningful gains in isometric peak force production within the trained joint angles, which adds to the existing evidence of joint angle specific adaptation—especially at short muscle lengths.
The improvement in isometric peak force production, however, failed to have a positive transfer to any dynamic athletic performance variable (SJ, DJ, CMJ, 40m sprint). The lack of improvement might be due to the not-yet-optimized coordinative and task-specific movement pattern. Without a concomitant and task-specific re-optimization of the coordinative pattern, a transfer of the training effect (i.e., greater force production) to any athletic performance task cannot be expected in such a short period of time. Therefore, only focusing on increasing force-producing capacities might induce, at best, no positive changes in any athletic performance over short periods of time. For me, this highlights the importance of continuously focusing on optimizing movement efficiency, independent of the task.
Freelap USA: What is your approach to hamstring injury prevention in team sport play?
Daniel Kadlec: Although hamstring injuries are a multifactorial issue, which therefore needs a multifactorial approach, you do your athletes a big disservice if you are not implementing Nordics in a progressive and continuous structure. There is just too much robust evidence on its effectiveness to reduce injury likelihood. In order to elicit further structural (fascicle length) and physical (eccentric strength) adaptations, adding some hip-dominant exercises that target the hamstring will likely be beneficial, as no one ever had hamstrings that were too strong.You do your athletes a big disservice if you aren’t implementing Nordics in a progressive and continuous structure to reduce hamstring injury likelihood, says @DanielKadlec. Click To Tweet
It’s at least as important as any gym work to ensure a progressive and continuous exposure to maximal sprinting speeds, while optimizing movement efficiency (i.e., limiting back-side mechanics and facilitating lumbo-pelvic synergies). Off the top of my head, there is evidence demonstrating that 3-4 30- to 40-meter sprints spread over the course of a training week is a sufficient volume to have a meaningful impact on hamstring health. On top of that, preparing the athlete for sport- and position-specific worst-case scenarios from a running-demands perspective is another aspect that shouldn’t be neglected.
However, even if we do all this to the best of our abilities, there is no 100% effective way to prevent hamstring injuries, as risk will always exist in sport. The only way to truly prevent any sort of sport injury is not to play and train, which isn’t an option.
Freelap USA: What are some key integrations of data into performance coaching or, in other words, what data is most valuable to S&C practitioners, from your experience?
Daniel Kadlec: Any sort of data that can inform your practice immediately, without having to do a tedious and time-consuming analysis first. Although the academic in me is always willing to collect as much valid and reliable data as possible, just in case I come up with a hypothesis in hindsight or want to reflect on my coaching, the practitioner in me deems it unnecessary and limits spending time and energy in this area to the utmost important and practically relevant information.Any sort of data that can inform your practice immediately, without having to do time-consuming analysis first, is most valuable to S&C coaches, says @DanielKadlec. Click To Tweet
My go-to data source during the session is everything that can maximize the output of the targeted exercise via augmented and objective feedback, be it sprint times, jump distances, RSIs, or bar velocities. Athletes like to compete. Although most coaches rely solely on verbal and subjective coaching feedback and/or rudimentary testing references—and this worked perfectly fine before the influx of microtechnology—providing something extra can optimize your training efficacy in some circumstances.
Further, having basic wellness (sleep quantity, sleep quality, soreness, mood) and load-monitoring data (RPE post session + ACWR) can add and confirm what your coaching eye sees in terms of deviating from the individual movement patterns, unusual excessive stretching/foam rolling routines, and/or any other noticeable changes in behavior, which can therefore be the starting point of a conversation with the athlete and/or coach.
However, as long as we coach people, all the currently available systems to collect and use data are cool, but they do not replace having or building towards a true and genuine relationship with your athletes. I’d like to get to know them first and use any other resources only as an add-on.
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