Plyometrics for Speed Development

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By Carl Valle

A goal of this article is get right to the heart of the matter, using jump training to improve the outcomes of speed and power programs in sport, specifically track and field and team sports that involve running and jumping. Most of the information included here is coming from big names and some less known individuals who I feel are successfully designing workouts that involve selective application of explosive exercises. I have attended workshops from Dan Pfaff, Boo Schexnayder, Dick Booth, Randy Huntington, Dave Kerin, and Jimmy Radcliffe personally. In addition to those examples of experts, I have privately visited and questioned different coaches such as Tom Tellez, Håkan Andersson, and John Smith. Countless other names I have heard lecture or read their materials, and have seen a lot of commonalities and some unique perspectives. After a few months of asking coaches in sports performance, I was surprised on how many requests for plyometric training information was coming from both track and field and strength and conditioning. I didn’t have concrete answers because I don’t have expertise or a lot of experience, but I did have good questions and observations of trying what others have told me. The information below is a commutation of years of trial and error, sometimes painfully ineffective, and I hope it will stimulate discussion.

Plyometrics for Speed, Jumping, Agility, and Injury Prevention

The primary four reasons we use jump training to improve performance is not a mystery, but how effective jumping or explosive exercises are precisely is unknown. It’s not rocket science to expect that jump training will help jumping, but where specifically jump training helping to reduce ACL injuries or improve maximum velocity is murky. Doing any exercise is not a the Holy Grail, but some patterns of success can be seen when doing commonly prescribed progressions of exercises and integrating them at the right times and sequences. Eccentric strength has a high success rate with preventive care by preparing for success instead of avoiding danger. Agility has similarities to injury prevention but the absolute goal is consistently having better redirection qualities than one’s competitor. Some statements I believe to be true are as follows:

• Plyometrics help athletes become durable from strengthening some tissues and prepare the nervous system for similar contractions later.
• Plyometrics are alternative options to sprinting but are not replacements entirely.
• Plyometrics help deceleration or agility by overloading the eccentric actions of sport movement.
• Plyometrics are specific to jumping, but are not always appropriate to jumping sports if other elements are not included, such as running and maximal strength.

In this article we will focus on the most elusive of qualities, speed, since plenty of program exist on reducing ACL injuries and increasing your vertical are available, but the improvements of speed is the most captivating.

Plyometrics and Maximal Velocity, is it worth it?

The research and experience of wise coaches is mixed on how jumping exercises can make one faster. The charts by Al Vermeil were clearly showing how acceleration can be improved by different modalities, but at top speed the options are few. Several studies show that early and late acceleration is aided by plyometrics, but maximal speed has yet to be shown to improve by jumping exercises with elite sprinters. Many reasons exist why studies are lacking, such as controls and the limited amount of elite sprinters willing to participate. So, two problems exist with trying to crack the code in maximal speed. First, are the designs of most studies being with novices and being short term. Adaptations to speed take years and that means a convenient study of 8-12 weeks isn’t what we need to explain what coaches are doing over seasons. Second, elite athletes are not gong to respond as well because the gains are already acquired from years of sprinting, so the question is how much faster will someone run using sprints.

“The benefits of plyometrics for sprint performance are expected to be the greatest at the velocity of muscle action that most closely approximates the velocity of muscle action employed in training. Therefore, it has been suggested that the greatest effects of plyometrics on sprinting performance occur in the acceleration phase, since the velocity of muscle action in bounding plyometric exercises most closely approximates the velocities of muscle action in the acceleration phase of the sprint.” — Goran Markovic and Pavle Mikulic, “Neuro-Musculoskeletal and Performance Adaptations to Lower-Extremity Plyometric Training”

So it doesn’t matter if people are using 6 foot depth jumps if none of them are breaking 10 seconds in the 100m dash, since the goal of plyometrics is to offer something sprinting can not do. Perhaps elites may benefit from creating a new stimulus or overloading specific regions or firing patterns but none of this is clearly proven to work. When athletes start to hit their genetic ceiling and plateau, the more likely the bigger the risk one may be tempted to take to break through that speed barrier. Without any understanding of what non-specific exercises like jumps have on specific problems, we are seeing an array of plyometric exercises, usually ones that mimic or grossly emphasize the force demands of sprinting.
Maximal Velocity and Terminal Acceleration

One of the best presentations on sprinting I have seen was in Sweden a few years ago when Jon Goodwin was requested to present on his findings that made many rethink conventional stride length and stride frequency, and what really are the limits to running faster.

“It would seem that an inability of athletes to continue to increase peak vertical force production [due to diminishing contact time] gradually reduces available vertical impulse until airtime reaches a practical minimum. The athletes cannot run any faster because they won’t be able to generate sufficient [appropriate] airtime to recover their swing leg [and optimize stride length].” — Jon Goodwin, “Maximum Velocity is When We Can No Longer Accelerate”

The description by Jon was very enlightening, because the simple priorities of not falling on your face from lack of time to reposition the leg is more important than additional speed, provided the resultant forces are producing the right applied power. However the body is able to coordinate the very precise and rapid needs of keeping the body balance is marvelous, since all of this is completely reflexive and done at the near spinal level. Additional speed horizontally is secondary, since gravity and balance, like it or not, trumps the request for additional velocity.

So the question is how much can we change what happens at 0.080 seconds per foot strike. For changes to improve speed, we basically need to do more work in less time, or theoretically more efficient work in the same time. To illustrate this clearer, elite sprinters have shorter ground contact times on average to lesser counterparts and that means they are able to apply more force faster in general. Another idea is what is going on with individual limbs and foot motion within the .080 time period? Can we improve that slightly so we are overcoming gravity faster with more stiffness in order to get more hip extension and potentially less braking forces? Most likely not since more stiffness earlier will likely increase braking forces since the swing leg must pass close to the center of mass, do the necessary work on the ground, and pass through the hips and recover back again. Early and high stiffness with the foot contact in front of the center of mass may increase horizontal breaking forces so that propulsive and vertical forces are not enough to increase speed. Years ago at the same conference but different year, noted authority PJ Vazel showed ratios of body heights to stride length, hinting that some relationship exists based on one’s body type and the stride characteristics. He also showed development of frequency and stride length, general characteristics but important, with long-term development. It may be fair to conclude the body needs sufficient speed and power at foot stride to take care of priorities (not falling) in order to then have time and energy to create additional forces for increased velocity. So far many coaches and some online personas have tried to solve this kinetic and kinematic puzzle, but no conclusive evidence of what can be done to consistently improve maximal speed without running maximally.

Sprinting 28 mph, Reaching 12.5 m/s, or Hitting a 0.80 Split?

If you were to observe a track meet, specifically a sprinting event, it wouldn’t take much to see who won and what time they got in the race. Coaches on the other hand want to know why and how they achieved their times with further analysis. When I look at the influence of any modality, a return on investment based on risk and reward is always pondered. Some coaches have looked at electrical muscle stimulation, specific exercises in the weight room, overspeed devices, and even hypnosis to get people to run faster. Some of it works and some of it not only fails to work, but is dangerous. The question one should have is the following: how much influence does any one element, or a component of one element, have on measured speed changes? I like the idea of seeing how practice times and meet performances change based on chronic use of an option such as plyometrics and sprinting. Therefore, I suggest looking at flying sprints in practice and splits during meets to see where the improvement is within the race and the improvement of the modality in general. It is unlikely that lack of improvement in jumping will equate improvement in sprinting, since improvement in jumping has not always shown to improve speed development, no matter how well it’s coached or trained.

Theoretical Use of Plyometrics and Speed Development

Plyometrics are effective for some athletes and might be contraindicated for some, but generally dong some rudimentary jumping is a good idea, since the demands are safe enough for everyone. Defining plyometrics should not be limited to the rule of one or more authority, because elastic responses from any training option is likely to have a small role in speed. Therefore a few medicine ball throws may not directly influence the rate of force at top speed, but it may help warm an athlete up for better speed practices. In fact many options, bounding, hopping, skipping, jumping, drills, and sprint options are all plyometric, but most options are only effective in early acceleration as stated earlier. It’s likely that early acceleration, or slower contraction rates, are more effectively improved by plyometrics. A recent series of studies on sprinting and weighted sleds showed similar improvements to speed to plyometric options. Like plyometrics and contraction times, lighter loads help with faster velocities and heavier loads help with earlier acceleration (slower and longer contractions). How much better heavy sleds are versus heavy or explosive weight training is perhaps is something to think of before overloading speed. With any distance rehearsal of fast sprinting at all of the distances is wise. One study using light, medium, and heavy loads, the lightest load helped the later segments in the sprint and the heavier loads influenced earlier parts of the acceleration, demonstrating the specificity of overload. The research on sleds supports earlier notions that Al Vermeil listed after summarizing many different experts with regards to how to improve speed specific to the distance one is trying to enhance. A good rationale is that as the distance increases and the velocity rises, the options should include exercises that try to produce high forces with less ground contact time.

Single and Double Leg Options and Horizontal and Vertical Jumps

Specificity and different neurological claims have been made to support various ideas on what plyometric exercises will transfer to sprinting. Sprinting being an alternate explosion of leg movements naturally seem to conclude that bounding, alternating explosions between legs, would be more specific and be a better option than double leg jumping. Three mistakes are made when people drive specificity too much and here are some guidelines to why we need focus on the adaptive changes in speed, rather than focus on hypothesis of dated training theory:

1. Single leg training is anatomically specific but visual replication may not matter when rate of contraction and other factors may require a bilateral movement to improve the results or outcomes. A double leg jumping routine may have kinetic (forces) similar to sprinting but hopping (single leg) may be to slow or the rate to long for it to be effective.
2. Horizontal jumping exercises may be great testing battery but all jumps exercises done for distance do need sufficient vertical forces, making interpretation difficult. When technique hits a plateau, the data is more valid and it’s a useful measure of eccentric abilities.
3. Stiffness jumps are great ways to work on minimizing ground contact time via rapid contractions from short amplitude work or joint angles. Many neuromuscular adaptations are not fully understood currently, but adding more general power doesn’t mean it can be applied faster.
4. Heights of depth jumps don’t equate to speed abilities so it’s important to ensure that the athlete is able to absorb and transfer effectively the forces by their own contributions. A good rule of thumb is making the rebound in one’s center of mass (COM) as high as the original starting height.

Popular Training Theory and Plyometric Training Design

A near countless set of ideas of the best progressions, regressions, sequences, and alternate options exist in current training theory. Many coaches will look at volumes, type of movement, coordination demands, and even theme of the training to program jump training. When coaches are trying to merge sprinting, general training, strength work, and plyometrics, the most basic variables are often brought up. Total round contacts, weight of the athlete, order of exercise, the use of equipment and external loads, and other common variables are decisions that must be decided or taken into account.

I am not a fan of segregating exercises because sometimes a movement or drill has multiple benefits and roles. Arbitrary or convenient theories of organization are also a possible path to nowhere, like the idea of placing jumping exercises up on a box in the beginning of the season to help with acceleration or thinking maximal speed should be paired with speed hops. For years I have seen amazing and brilliant explanations for what theoretically may help development long term, but with speed development, the details of jump training are just to marginal to be a real gain in performance. Thinking that specific details of a few training sessions will create a real world adaption is just wishful thinking. Planning out a jump program that is safe and logical is a different story. The cumulative effect of training is real, but only over years will a program reap impactful changes to top speed. Just a 1% improvement is a great enhancement, so the specifics of one part of such a change is fractions of a percent, something too small to be chasing. A realistic approach is to ensure safe loading approaches and logical ways to pair the plyometrics to a comprehensive program.

Three Elements of a Good Training Program

Testing and Evaluation — When inheriting an athlete, objective performance and a more qualitative evaluation is needed to see where one needs to begin. Ability and skill are not the same, since many athletes are great athletically but lack the fundamental jumping skills to safely overload. A big difference exists between an athlete who can dunk fluidly but never was taught to engage their hips in bilateral jumps from a box. Measurements from tests are only useful when they can do the activities or exercises properly, but underpowered athletes are part of the assessment and single leg right to left testing is highly recommended. A good argument when screening or testing is that performance measurement with technique evaluation is not mutually exclusive, and if done right are natural pairs. During the evaluation process coaches should see what athletes are familiar with (terms and naming convention) as well as basic ability to follow direction.

Slow Career Progression — Plyometrics are frankly dangerous if not implemented correctly and ground contacts or even scales of intensity are not enough to precisely quantify specific load. Teaching landing positions and doing in place exercises such as tuck jumps and scissor or split jumps is enough for most neophytes. It’s tempting to progress too fast because athletes are sometimes quick learners but tendons and connective tissue doesn’t remodel at the rate of learning. Athlete’s talents are often their biggest downfall, so slow progression with an emphasis on technique will be the best path in year two. Year three is when output can be challenged, but slowly and carefully. It’s easy to add more, longer, heavier, and higher, but it’s smarter to do it better with a focus on efficient application.

Individualism of Application — Eventually athletes will progress to the point that fundamentals are acquired and general qualities are no longer applicable. Individualized training is appropriate when unique needs must be selectively administered in order to make progress. Some athletes don’t tolerate jumping while some thrive, so it’s important to always test and measure the maximal speed to ensure improvement is stemming from the plyometrics. With training one can’t really create a control group because if you truly believe something works you have to in all fairness allow everyone to have access to the training methods. A workaround is seeing improvement in jumping and expecting some sort of transfer in training, even if it’s extremely small. Analyzing the running data one can start seeing if the program needs adjustments by supporting modalities such as plyometrics.

Teaching and Instruction of Plyometrics

In the final installment we will get into the actual coaching side of plyometrics. The goal of a good design or program of jumping is to minimize the teaching and go directly to athlete revealing their abilities. Cueing, instruction, directing, are very coach centric, and the masters tend to more like guides versus drill sergeants. In the third article every exercise will be explored and reviewed so coaches who are not comfortable with plyometrics can effectively implement the training with some timeless guidelines. It is suggested to visit and work with other coaches who are teaching the exercises day in and day out rather than learning from videos and online articles.

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