What is Plyometrics?
The goal of using plyometric training is to attain maximal muscular power in the shortest amount of time. This type of training is most beneficial to sprinters, and athletes who require fast acceleration. Plyometric injuries most often occur due to athletes doing too much too soon, or by incorrect technique of the exercise. Things to consider in order to reduce the likelihood of plyometric injuries:
– land on the largest possible surface area of the foot by landing on toes before softly rolling down onto the heels .
– plyometric exercises are normally only recommended for advanced and experienced well-conditioned athletes.
– take long rests between sets and always stop when feeling overly fatigued.
Plyometric rehabilitation: Using plyometrics for rehab
Explosive power training has a role in therapy programs. Plyometric drills and exercises have been used to enhance athletic performance for decades. In rehabilitating my own clients back to a safe and successful return to sport after injury, I believe plyometric training is an essential component.
The literature available on plyometrics is not conclusive. The research does not validate the effectiveness of plyometric exercise in the prevention of reinjury, or whether it promotes a more successful return to sport. Plyometric training is becoming more popular for the upper body, but the available research only looks at lower limb training. Although the available research is inconclusive, this should not deter therapists from using it within the rehabilitation program. However, a thorough understanding of plyometrics is required.
The science of plyometrics
The neuromuscular system is worked very powerfully during plyometric training, with the aim to make the muscles work more in less time (7) by increasing the elastic properties of the muscle-tendon unit to increase explosive power.
The difference between plyometric training and normal strength training is its focus on improving the efficiency of the stretch-shortening cycle.
A plyometric movement can be divided into three phases:
- The loading phase –If we look at a ‘tuck jump’ plyometric exercise as an example (where you jump up and pull both knees towards the chest while in the air), the loading phase is when you first hit the ground before repeating the jump.
- Coupling Phase – This is the brief moment of transition between the loading and unloading phases, when joint angles and ground reaction forces are about to change direction. During this time, the muscle-tendon complex length is constant and the muscle is in a state of isometric activation.
- Unloading phase -This is the period from when the muscle-tendon unit begins to shorten (concentric contraction) through to when the foot leaves the ground (lower limb) or when a resistance object such as medicine ball is released (upper limb).
Researchers have identified a direct correlation between plyometric training and the following improvements in athletic performance:
– increase in vertical jump height
– improved sprint times
– increase in golf speed and driving distance
– improved running economy.
When to start plyometric training
An athlete should be able to perform functional movements such as a double and single leg squat before they attempt plyometric training. If you can’t squat properly, you certainly won’t be able to do a jump squat effectively, and will greatly increase your risk of injury.
The role of plyometrics in rehab
The key training principle of specificity dictates that training for a sport should replicate the movement patterns and energy systems required for that sport. Since the aim of rehabilitation is to regain the pre-injury level of function of the injured site, specificity would seem to argue in favour of using plyometrics as a rehab tool. If an athlete has to run, jump, and change direction in their sport, then their rehabilitation should prepare them specifically for those actions. The crucial judgement for therapist lies in what level of activity to introduce at what point in the rehab process.
Therapists should be aware that there is a risk of aggravating injury with plyometric exercises during rehabilitation. However, I believe if the athlete returns to play an explosive sport without having performed plyometric exercises at a high level, they will be at greater risk of re-injury.
How much and when
Low intensity plyometric rehab can be done daily as long as the exercises don’t provoke soreness to the injured area. I recommend that high intensity exercises should only ever be done every second day at the very most. If an athlete is able to perform high level exercises, they are most likely to be a week or two away from competing, and then they can resume their normal training regime.
I believe this modality is essential to the success of late stage rehabilitation. As long as the exercise is mimicking the sporting activity and you are confident the athlete’s injury can withstand it physiologically, embrace it.
To learn more about plyometric training, please contact Kalgoorlie Physio on ph. 4972 5155. Shayne has been providing physiotherapy services to Gladstone for the past 5 years.