The following article will briefly discuss the history of plyometrics, outline the specific differences between what is considered true/ fast plyometrics and what is considered to be slow plyometrics/ jumping, how to prepare and programme plyometrics or jumps into a training programme and what desirable effects they have on the athlete performing them.
Where possible I will reference studies or the experience that has been passed onto me.
Firstly I would like to address that not every athlete needs to specifically do intensive plyometrics as a method of training. It is widely reported that Clyde Hart had never prescribed plyometrics to Michael Johnson, though he still held and broke multiple WR’s.
This is likely because the quality, intensity and contact volume in his training was sufficient for him to be incredibly reactive on ground contact.
However, if you could improve your ground contact time, as many athletes could, it is likely you will run more with more efficiency and faster.
Finally, due to my limited memory, attention span and time, I cannot go into every method with extensive detail, but I will do my best to cover everything an athlete or coach may wish to know if they are considering the addition of jump and plyometrics to their training programme.
Brief History of Plyometrics
It’s orgin stems from the great USSR biomechanists & sports trainer Yuri Verkhoshansky, he worked with the Soviet national sports teams for the Olympic Games and is credited with developing the training methods to stimulate the stretch-shortening concept of muscular contractions.
In 1975, USA Olympic long-distance runner Fred Wilt observed the Soviet Union perform jumps in their warm-ups prior to their events.
To describe them, Wilt coined the phrase ‘plyometric’ and after consulting with performance coach & researcher Dr. Michael Yessis, Wilt discovered that the jumps were based on research being pursued by Verkhoshansky, called his ‘Shock Method’ of training, which I will discuss further on.
If you’re interested in learning more about Verkhoshanky’s work, the following link, covers pretty much everything in far greater detail than this article.
The Stretch Shortening Cycle (SCC)
There are three phases to a plyometric movement, for this case we will be looking at jumping.
- The descent, or eccentric phase
- The amortisation phase/ phase where the change of direction occurs and
- The concentric phase, which leads to the take off.
The faster the athletes, the faster they can push and change direction from the first phase and the quicker the second and third phases are.
The stretch shortening cycle (SSC) is a trainable, dynamic reflex that loads the tendons and fast twitch muscle tissues that produces a rapid eccentric contraction (the stretch, where elastic energy is stored) before the muscles/tendons stop the lengthening and changes direction to a concentric action.
The shorter this phase, the more powerful the muscular contraction will be as a result.
This is what creates the appearance of stiffness through the movement.
The greater the athlete descends, the greater the overall GCT and the more range of motion the athletes muscles go through, which allows them to create a more muscle driven jump.
This is why athletes who are incredibly strong will often jump their highest by going deeper on a vertical jump and why high jumpers produce their best jumps through a shorter range of motion, as they are more elastic and respond very well to loading their tendons.
Myogenic and Neurogenic Adaptations
Generally speaking, the majority of plyometric exercises/ jumps work by developing the tissues, muscles, tendons and fascia surrounding the lower limb and foot complex.
The achilles and foot act very similar to a spring and as the athlete continues to develop their plyometric ability, two very important adaptations take place.
However, these adaptations do take time and plyometrics should always be performed when the athlete is relatively fresh and has the ability to react off the ground.
Myogenic adaptations occur within the structure of the soft tissue as their elastic potential energy increases through improved tissue density.
This will allow athletes to store and recoil energy more effectively and why having a powerful, thick achilles tendon is desirable for running.
Neurogenic adaptations take place through repetition of movement and as the athlete’s efficiency improves, as does the rate of firing the motor units required to perform the SSC.
To reap the greatest benefits from these two adaptations it is important to progress with a variety of exercises to learn the rhythm and timing whilst balancing intensive and extensive plyometrics for the best results.
The Differences Between Fast/ True Plyometrics & Slow Plyometrics/ Jumping
During 2013-14 I had the good fortune of learning the majority of what I know, practically about plyometrics from an Ex Commonwealth games High Jumper, Rob Mitchell who had a High Jump PB of 2.25.
He taught me the basics to bounding, jumping and hopping, on the flat and my personal favourites, on a hill, both up and down and to this day I still programme these exercises to my athletes.
Unfortunately I was a bit late to the party and only really learnt plyometrics properly during my final year of athletics and wasn’t able to capitalise on what I had learnt.
Much of the work I learnt from Rob were, true plyometrics, or fast plyometrics.
Prior to his training sessions I had only done slow plyometrics, or what I would consider now to be, just, jumps. Your typical box jumps or vertical jumps.
Which only really assists the concentric phase, or take off during the jump and that’s only ⅓ of the movement and the preceding actions lead to the take off, so as you can imagine my timing was awful.
I was able to jump fairly high but my ability to react off the floor was pretty poor, meaning I wasn’t very reactive.
To improve reactivity, it’s important to be performing and progressing in the fast plyometric exercises, which I hadn’t been doing.
True plyometrics, or ‘fast’ plyometrics occur with ground contact times of 0.250m/secs or faster.
This means for a beginner with limited reactivity will have to limit their falling height as the higher a beginner falls the greater their contact time will be.
What I had been doing was slow plyometrics or standard jumps and these take place above 0.250m/secs and thus their ability to transfer to shorter GCT, such as sprinting which takes places around 0.8-9m/sec are less successful.
I wasn’t teaching myself to react off the floor, or to push fast enough through my jumping as I prior to the help from Rob, I was learning slow plyometrics.
As coaches/ athletes how do we measure these GCT’s?
Before force/timing plates came into existence coaches would clap to to monitor their GCT, the athlete would have to land, react and take off all in the time taken for the clap to complete.
This can also help the athlete keep to a rhythm which is half the battle with extended plyometrics for beginners.
If you’re interested in readings for GCT’s over various activities see table 1 below.
Note: Counter movement jump is a standard vertical jump, where the athlete loads the jump with their arms from the descent.
Progressive Plyometric Development
As for developing a programme, this is very much down to the coach and individual. If you’re interested in creating your own plyometric programme, the brilliant team at Strength of Science have compiled a really useful infographic you can use, or if you would like any more information on how to structure jumping and plyometrics in your training, feel free to contact me.
I would also like to note, from further research listening to some of the best jumps coaches in the world, my view on practicing landings and ‘force absorption’ has changed and I no longer see value in practicing landings to stick landings, the landing technique should be a natural reaction to applying force on contact and having an equal and opposite reaction and not by absorbing force.
Common mistakes and misunderstandings within Jumping/ Plyometric
Before I finish, I feel as though passing on some of my previous mistakes will help others learn faster.
It’s always important to know why and how to perform and exercise in order to reap the best results, context here, as always is everything, but I want to address three mistakes I was guilty of early on and three of the most common mistakes I see on social media.
- The box jump, stacking boxes higher and higher not only favours a taller athlete, but also favours those with greater hip and ankle mobility and their likely to have a better box jump in relation to their vertical jump test.
This doesn’t mean to say that an athlete doing a really high box jump, cannot jump high, it’s likely they’re still a good jumper but mobility really helps for the landing and the most transferable athletic element of the jump is the distance travelled by the hips, not the feet.
You are much better off using a smaller box and trying to land as high as possible on that box for the greatest hip displacement.
- The depth jump, again going too high and trying to react off the floor will result in less reactive contacts and a greater contact time, it is much better to progress slowly for these and aiming to react as quickly as a clap.
- Treating the movement mechanically. Though there is obviously a technical element to plyometrics, setting up the jump efficiently through take off requires rhythm and the quicker an athlete learns the rhythm the faster their progression will be.
Plyometrics should be fast and dynamic and being too static and mechanical will remove the element of fluidity and affect timing.
Plyometrics for Distance Runners
For a period when I was helping a distance runner with their gym work I programmed in plyometrics, which is a tough sell for endurance athletes because it’s commonly assumed to be useful for sprinters and jumpers.
However one study (Paavolainen et al., 1999) on well trained endurance athletes found that replacing just one-third of their normal running with plyometrics improved their 5k race times. The 18 runners in the study underwent the same total training volume over a nine week period but 10 of them had 32% of the running replaced with plyometric training. Following the nine weeks, the 5K time of these 10 runners improved whereas no changes were observed in the other 8.
The Foot and Ankle Structure
Just briefly before I finish, I wanted to cover one of the more important elements for transferring force through the lower body to the floor.
The foot, toes and ankles are easily forgotten about when developing athletes but the reality is, if an athlete can get stronger toes, feet and ankles, their ability to react and transfer force into the floor will improve.
Strong feet have strong arches and strong toes.
But it is important to understand that this does not mean an athlete with flat feet has weak arches, they can have incredibly strong feet but genetically have a low arch height.
The strength of the arch comes from the development of the muscles and tendons surrounding the toes and ankle and each foot has more than 100 muscles.
Strengthening the foot and ankle complex should also be done through reflexive/stabilising exercises.
Stabilising exercises help the intrinsic, smaller muscles support the arches and ankles to create balance and the more stable a joint is the greater the efficiency of transferring force due to less energy leakage and the less likely an injury will occur due to compensation, especially through fatigue.
Exercise to strengthen the feet and toes
– Walking barefoot and being conscious of the big toe and the glute (hip) working together.
– Performing barefoot calf raises, either slowly, or with a hold at various heights and ensuring to push though the big toe and pulling the smaller toes up.
– Barefoot low intensity bounces on the toes
– Toe curling/ gripping exercises
– Single leg balancing exercises to failure
If you’re interested in learning more about developing the feet, toes and arches, I highly recommend learning more from Chong Xie at https://www.secret-of-athleticism.com/
I’ve been using his exercises now for several months and my feet and contacts feel as reactive as when I used to jump four days a week, where I was weighing 15kg less.
If an athlete has slower than desirable GCT and they regularly work on developing the strength of their toes, feet and ankle stability, alongside regular, progressive and varied plyometric exercises with sufficient recovery and rest, they will develop greater reactivity off the floor and produce larger forces through faster GCTs, leading to higher jump heights and faster sprinting speeds.
If you feel more fatigued from doing the plyometrics than when you started, it’s likely that you have done too many contacts.
The SSC is the most specific transferrable element to athleticism, there are multiple ways to train the SSC, whether it’s through running or weight training, athletes can still progress and develop without one and nothing is more specific or transferrable than the event itself.
I believe every coach should be addressing the SSC outside of running/ sprinting and most research now suggests complimenting plyometrics with strength training, either through French Contrast Training or similar methods working through the Force Velocity Curve with Velocity Based Training.
If you have any questions on training and performance, feel free to email me on firstname.lastname@example.org