For me, 2018 ended on a surprising note: One of the sports coaches I work with came down to my office and asked how I utilize sports science while working with his team. To help you appreciate how stunned I was by this inquiry, this coach really doesn’t like using technology. As a matter of fact, each fall I still get passed the team roster with positions, hometowns, and school ID numbers in a handwritten note. When I’d previously suggested the coach could use the same Excel document all the other teams use, I was essentially told that Excel was too difficult to figure out. Now, don’t get me wrong, this coach runs a successful program; still, the mindset is very “old school,” so being asked about how I use sport science was a major happening.
As happy as I am to have deeper conversations with sports coaches about what we do with our athletes, to have a person who struggles with basic computer programs like Excel turn around and ask about sport science left me with more questions than answers. What inspired the coach to suddenly ask about sports science? What sort of answer was he expecting from me? Was this conversation based in some sort of trivial curiosity, or was there a genuine interest in discovering better information?
When I think of sports science, there is a very specific scene from Rocky 4 that pops into my head: Russian boxer Ivan Drago strapped into machines that measure all sorts of kinematic data from his movements, under the watchful eye of scientists in white lab coats. Maybe this is what the sports coach had in mind when he asked about how we use sports science.At its core, sports science is collecting information and objectively coming up with decisions. Click To Tweet
I think the reality of what sports science is would have really come as a surprise, since at its core sports science is just collecting information and objectively coming up with decisions. This is what we’ve been doing for over a decade, all while wearing gym attire. You can spend some serious money on sports science tools, falling into the same trap I have: You see a piece of equipment that is super fancy, has a highly interactive display, and can measure a result very accurately. After budgeting for this piece of equipment, you eventually make the purchase…but when you begin to use it, you are totally disappointed. It’s not that the equipment doesn’t work; it’s just that it’s too complicated, takes too long to set up or test people, or the worst-case scenario: A $5,000 piece of equipment gives you $0.50 worth of information.
Most of the sports science data we collect is from athletes performing simple jumps. For my program, we capture all of this information on a Probotics Just Jump Mat, which costs about $600. All the athletes must do is stand on the pad, jump, and land. The handheld computer takes in a bunch of information, then delivers jump height and hang time, or whatever function you are looking for. I will say this—as with every test, there are ways to cheat this (like pulling the knees up while jumping). But as long as you have people do the same thing every time you use it, then you can compare RELATIVE data, not ABSOLUTE data. I’m okay with that.
Eventually, there is a time when we need to look at the absolute jump height of our athletes, and then we bring them down the hall to our Exercise Science program and use the program’s motion capture system to look at hip height displacement. Since that is hard to coordinate and it takes significantly longer to test the athletes, I’m okay with using the relative data we get from the Just Jump Mat. If you aren’t in a position to spend money on a Just Jump Mat, you can make an adjustment and change the following tests from a vertical jump into a horizontal jump. Then, the only piece of equipment you’ll need is a 100-foot tape measure.
Static Jumps and Counter-Movement Jumps to Assess Strength vs. Power
At some point in your career, you will run into someone truly exceptional and then you may scratch your head, trying to figure out what to do with them. Should you spend time training them at low velocities, working heavy movements like the traditional eccentrically loaded powerlifting events? Or, should you spend training time working the high-velocity movements like plyometric drop jumps or reactive-style (otherwise known as dynamic effort) back squats?
It would sure be nice to have someone or something tell you what areas you should spend time working on. The good news is there is just that sort of thing out there, and it is really easy to add to your testing battery. All you need to do is have people perform two different types of jumps and compare the results. Okay, okay—admittedly, there is a little more involved in the tests than that.
If you are using a jump pad, begin by having the athlete do their jumps with their hands on their hips to isolate the lower body as much as possible and eliminate the significant contribution generated by the upper body arm swing. From that position, athletes will perform the more difficult of the two jumps: the static (or isometric) jump.
Video 1. A demonstration of the static (or isometric) jump done correctly. The athlete holds their jump stance position for 3-5 seconds to eliminate any stretch-shortening cycle benefit.
Video 2. A demonstration of the static (or isometric) jump done incorrectly. Watch out for athletes who perform a counter-movement hip drop to get a higher jump on their test.
For the static jump, the athlete assumes their jump stance, but then holds that position for 3-5 seconds to eliminate any stretch-shortening cycle benefit (more on this in a few paragraphs). The difficult part of the static jump is that the athlete has to have one single “push” that causes them to jump. Most people perform a little counter-movement hip drop in order to get a higher jump from their static jump test, which is something you need to coach them out of.
The next style of jump for the test does take full advantage of that counter-movement hip action: One that is, as you likely already know, called a counter-movement jump. As in the static jump, the athlete again prepares to jump with their hands on their hips—but in this jump, it is all about a rapid drop to their jump stance and immediately jumping from there. If you are thinking that the counter-movement jump sure sounds like the athlete is tapping into their stretch-shortening cycle, congratulations, you are correct! If the stretch-shortening cycle is something new for you, let me give you a brief overview.
Video 3. With the counter-movement jump, the athlete taps into their stretch-shortening cycle. After preparing to jump with their hands on their hips, they rapidly drop their jump stance and immediately jump from there.
When you stretch a muscle (called an eccentric load), the stretch can store up some of the mechanical energy in the tendon and ligament that interact with the muscle. This is not only something discussed in exercise physiology, but is also one of the laws of thermodynamics in physics, known as the conservation of energy. The catch is, in the human body we cannot store this energy indefinitely, which means you will lose this energy in less than a second.
Let’s say, however, you quickly stretch a muscle and act quickly. Then you can use this stored energy AND tap into a nerve that causes your muscle to contract even harder and faster than it could without the stretch. Think of a squat: You can lift more weight going down (the stretch) and up than you could if you started with the bar on the safety rails and only brought the bar up. This is what the stretch-shortening cycle can do for you. Not bad, huh?
Where the Data Comes in
By comparing the two types of jumps (counter-movement and static), you can create a rough idea of what Dr. Zatsiorsky refers to as the “explosive strength deficit” in Science and Practice of Strength Training. The explosive strength deficit (ESD) is a comparison of how much force can be produced with (counter-movement jump) and without (static jump) tapping into the stretch-shortening cycle’s benefits. This is something that you have to check on a regular basis, because the ESD is a ratio and it always responds to how you program workouts. At some point, the athlete is overpowered for their strength level and needs to get stronger at low-velocity, heavy strength work. At another point, they’re too strong for the power they can produce and need to spend time working on high-velocity exercises.The relationship between the CM and static jumps helps me figure out what qualities to program for. Click To Tweet
The relationship between the CM jump and the static jump is a part of how I figure out what qualities to program for. When you know the CM jump and static jump scores, you have to run a really simple equation:
ESD = 100 X (CMJ-SJ)/CMJ
That’s it. When you run this equation for the explosive strength deficit, you’ll get one of two possible results:
- If an athlete scores in the 0-10 range, that should be an indicator that you need to spend more time developing near explosive strength—specifically, strength that involves rapid counter-movements like plyometric jumps. People who fall into this group include athletes who are really strong, but can’t translate their strength to their sport.
- If an athlete scores greater than 11, it’s an indicator of being overpowered; they likely need to spend time doing some old-fashioned strength work. I understand that being overpowered and underdeveloped sounds like a contradiction in terms (since strength is a component of power), but remember we are trying to figure out which style of training can improve the athlete’s weakest attribute. In this case, there will be a much greater return on time spent focused on developing strength at lower velocities like deadlifts and squats.
|CM Jump||Static Jump||Equation||ESD||Suggested Training|
|Athlete 1||30”||25”||100x ((30-25)/30)||16.6||Low-velocity strength|
|Athlete 2||20”||19”||100x ((20-19)/20)||5.3||High-velocity plyometrics|
|Athlete 3||25”||22.5”||100x ((25-22.5)/25)||10.0||High-velocity plyometrics|
Repeated Jumps Test for Return to Play Protocol
I’ve been fortunate enough to work with college athletes for almost two decades now, and in that time, I’ve seen a lot of injuries. Some were due to freak accidents, like a broken leg from sliding into the boards in hockey. Others were from overuse, seen in muscle strains resulting from bad compensation patterns. Others still, like a sprained ankle, were injuries written off as simply part of the game. It never gets easier, seeing people you work with get hurt, and it’s even worse when they reinjure themselves largely because they tried coming back to the sport they love before they were ready.
We can get into a much larger discussion of why athletes come back too soon (and the reasons why they get injured in the first place), but for now I’m going to focus on the practical and pragmatic side. When there has been an injury that resulted in a loss of game time, professionals in our field should have a say in whether that athlete is ready to return to play. Correction: When I said should, I meant that people in our profession need to have a say about the athlete’s return to play status.
Coaches in the strength and conditioning field have the ability, education, and tools to measure how well athletes create, absorb, and redirect force. And, if you truly look out for the best interests of the athlete, reviewing their ability to create, absorb, and redirect force is the best indicator for not only return to play, but for identifying athletes with a high injury risk in the first place.An athlete’s ability to create, absorb, and redirect force reveals their return to play readiness. Click To Tweet
To determine this, you’ll need to find a way to test people’s ability to handle repeated acceleration and deceleration. In my experience, when people are getting close to returning from an injury, they can usually compensate well enough during bilateral or even some unilateral tests. However, when the injured athlete attempts to jump and land repeatedly—now THAT is a revealing test. You’ll know simply by watching if the injured leg can safely handle the transfer of energy from landing to jumping as fast as they can.
If the athlete can handle the stresses of jumping, then they should be able to handle the stress of practice and competition without any increased risk. Basically, if I watch an athlete who looks like a superball bouncing when they do their repeated jumps, I am comfortable with them continuing their normal work. On the other hand, if the athlete bounces more like a tomato, well that’s an indicator that something is wrong and the next step is a conversation with the athlete to find out more.
Again, the athlete starts on the jump pad with hands on their hips, and jumps repeatedly as high and as fast as possible for four jumps. If you do this as a broad jump, the setup is the same, but they are trying to jump forward as far as they can, sticking their final landing. This will either give you a ratio number on the Just Jump Mat of their jump heights and ground contact times, or if using the broad jumps, a total distance. In both cases, the larger the number, the better the athlete did and the more “springy” they are.
To dig further into the data, you can have the athletes repeat the same test unilaterally. I must admit, it is fun to watch some of the football linemen attempt this single-leg quartet of jumps, but I do this for more than my own amusement. The comparison of right leg and left leg results very quickly shows any disparities and can help you focus on whether you should prescribe unilateral or bilateral training. My cutoff has traditionally been 10%: If the athlete is within that range, I feel comfortable with them spending more time doing standard bilateral work, since their dominant leg isn’t overshadowing their other leg, which is normal for that person. This is what it looks like in real life.
Video 4. If the athlete can handle the stresses of jumping, then they should be able to handle the stress of practice and competition without any increased risk. Here, an injured athlete performs single leg repeated jumps on her uninjured leg.
Video 5. This athlete is coming back from an injury to her left leg, and is yet unable to correctly perform the jump test with her injured leg. We adjusted her workout to include only unilateral leg training, giving the injured leg more volume than the uninjured one.
|4 Jump||Left Leg 4 Jump||Right Leg 4 Jump||% Difference|
In this example, you see an athlete I work with who is coming back from an injury to her left leg. Before the injury, she didn’t have any training restrictions due to the difference between her right and left legs. Basketball players typically have their left leg as their dominant leg if they are right-handed, and in this case, she had one of the lowest differences between legs.
Now she is getting ready to return from an injury to her left leg, and as you can see from the video and the four-jump data, she is far from being able to perform the test correctly. Not only are there practice limitations, but we have also adjusted her workout to include only unilateral leg training, with the injured leg getting more volume than the uninjured leg. The literature suggests that the greatest risk factor for sustaining a new injury is a prior injury. Therefore, if you have an injured athlete, you’d better make sure they are close to their pre-injury ability before putting them back in for competition.
Standing Long Jump for Athlete Monitoring
Over the past few years, I’ve become increasingly interested in ways to predict athletic success and create profiles for athletes (if you haven’t read any of those articles on the subject, you can find them here). During my trials of trying to design a universal way to objectively compare athletes, I looked at all sorts of variables, but I kept coming back to two things that any comparison needed to consider: There needs to be some expression of strength, and it has to be relative to body weight.Any comparison of athletes needs to consider an expression of strength, relative to body weight. Click To Tweet
Trying to come up with a way to compare strength might seem easy. At first it was, and I was set to use my go-to exercise: the squat. It seemed like a good choice, since the majority of my programming is centered around that exercise and the transfer of training it provides to speed or power. Plus, you can quickly come up with a relative comparison based off of body weight.
But, then I ran into a roadblock.
One of the fastest athletes we had at the school couldn’t squat. It wasn’t that they were weak, either physically or mentally, but they had a chronic injury we had to train around (a spondylolisthesis, also called a spondy). Basically, this athlete had some sort of trauma when they were younger, which caused a fracture in one of the bones of their low back. This college athlete’s broken bone would sometimes shift—which, from what I witnessed, was very painful—and that would severely hamper their movements. The No. 1 thing that triggered their spondy was squatting. High bar, low bar, or front squat: It didn’t matter what bar position we tried, anytime there was a bar putting pressure through their spine, it caused a flare-up and the athlete was in debilitating pain for the next few days.
How could I make a comparison when one of the fastest athletes at the school couldn’t even be included?
Obviously, this was a problem. If we had one athlete who couldn’t be accounted for in a squat test, how many more would be underrepresented because they are unable to perform a skill like squatting—not to mention an even more complex skill, like a clean? But a simple skill like a jump—everyone should be able to perform that if they are able to participate in competitive sports, right?
While I was at an NSCA clinic, long-time coach and colleague Dennis Kline from Wisconsin-LaCrosse was presenting, and it was like he was reading my thoughts. He talked about how he monitors his athletes simply by having them do a standing long jump. Here is the equation that Dennis shared:
Power Rank = (square root of body weight in pounds) x (square root of length of jump in inches)
Well, there was the answer I was looking for. Everyone should be able to jump without much coaching. This power rank also takes into account their body weight, so now we can tell an athlete if the weight they added (or lost) is helping them perform at their best. After playing around some with Dennis’s first equation, here are the adjustments I use for the variety of jumps introduced in this article.
Power Rank (Vertical Jump) = (SQRT Body Weight) x (SQRT Vertical Jump Height)
Power Rank (Broad Jump) = (SQRT Body Weight) x (SQRT Broad Jump Distance)
Power Rank (4 Broad Jump) = (SQRT Body Weight) x (SQRT (Broad Jump Distance/4))
These results have no units, they are simply a number—and the higher the number, the better the athlete is doing. The nice thing about this monitoring system is that you can predict a performance simply by seeing how the athletes change over time.This monitoring system lets you predict performance by seeing how an athlete changes over time. Click To Tweet
Below are two of the football players I’ve worked with this past fall. They are in the same position group, and both are starters. The first attempt was when football reported for pre-season camp, and attempts were done every other week during the season. Looking at the results some more, the second attempt was the first game week, and the sixth attempt was the second to the last game. When you look at these results, you can perhaps see that we had concerns about one of the athletes. See if you can come up with the same conclusions.
|1st PR||2nd PR||3rd PR||4th PR||5th PR||6th PR|
It can be difficult to have a conversation with athletes and their head coaches about their diminishing performance. This is especially true when the athlete is one of the more talented people on the team. But, as you can see in the example above, there was a constant decline in the Power Rank for Athlete 1. We were in-season, and the player had a constant problem: low effort during workouts, chronic dehydration, and he gained about 10 pounds (mostly body fat) by the end of the season.
It’s embarrassing for me to publicly talk about this decrease in performance, but part of this profession is asking the right questions when things aren’t working correctly. So, that’s what I did. I checked the results from others doing the same programs and they weren’t having the same decreases in their scores. The next step was to talk to the athlete. He freely admitted that his focus was on playing football, not lifting hard: “that’s what the off-season is for.”
It’s hard to do much for people who accept this type of mindset. Athlete 2 was mostly consistent with their Power Rank, with a dip in the middle of the season due to a leg injury. It’s funny though—during the post-season review with the football coaches, they did say how disappointing of a season Athlete 1 had had, and how happy they were about Athlete 2’s consistent level of play.
From Data to Decisions
If 2018 ended with such a surprise, I can only imagine what 2019 will bring. After all, if an old-school coach wanted to talk about how we use sports science with his team, who knows what will happen next? I do think this coach walked away with more questions than answers, but that is part of our wonderful profession. All coaches use their own creativity to dig deeper and hunt for the information that is important for their success. The take-home message with all three of these ideas is that there is a world of information available for you and you don’t need to be in a sterile lab wearing a white lab coat to find it.You don’t need a white coat and a sterile lab to discover all of the information available to you. Click To Tweet
What you want to do next is completely up to you. I’ve shown you examples for how to figure out what areas to focus on for the next stage of a program, how to figure out if an athlete is ready to return to full competition, and how to monitor athletes over time, because these are the things that are important to my program. You’ve seen two ways to test everything that I talked about, simply because I wanted to introduce something that you can immediately put into your program without making any sort of purchase. If you’re creative enough and passionate enough, you should be able to come up with a solution to any challenge you’re facing.
Right? Now go out there and figure out the best way to help the people who are counting on you.
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