Plyometrics are the great unknown in injury rehab. Firstly, they are difficult to execute and teach. And secondly, the benefits are rarely understood. However, how do we rehabilitate an achilles’ tendon if we haven’t trained the tendon to perform its most important role? The Achilles is a power amplifier, shock attenuator, and most importantly energy saver.
There's no doubt that calf strengthening is integral in achilles rehab, which improves the capacity of the tendon to handle load. However, once that capacity is developed, the focus needs to shift to retraining it's spring-like properties; maximising the tendons' potential to store and release energy. This is done through plyometrics.
Plyometrics allow one to retrain the ability to provide spring and elastic energy. This can not only increase the capacity of the tendon, but also shift vital load away from other injury prone areas, such as the knee.
An ability to minimise ground contact time when running is pivotal, as the elastic energy is only available for a limited time before it’s lost as heat. Being an overly compliant runner that spends too long on the ground results in the loss of elastic energy.
With these Achilles plyometrics we are aiming for a few things; short ground contact times, heel staying off the ground, minimal knee bend, ‘laces up’ when the foot is in the air, and a definitive, controlled, foot/toe 'strike' into the ground. If you turn the sound on you can hear when I strike the ground well into plantarflexion and when I do not - when the exercises get more difficult and single leg oriented the foot strike decreases. This is the most important part of Achilles rehab in my opinion
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