To jump or not to jump
Plyometric training uses quick powerful movements that involve the absorption, storage, and release of energy. In technical terms plyometric movements involve three stages; eccentric deceleration, stabilising amortisation and concentric acceleration.
Eccentric component: here the muscle is slightly stretched in a very short time storing potential energy. This is known as absorbing or yielding.
Amortisation component: this is a time of dynamic stabilisation where the muscles transition from overcoming deceleration and moving into acceleration. If this phase is too long the potential elastic energy can be lost and therefore the plyometric adaptations are compromised.
Concentric component: this is where the elastic energy is unloaded and acceleration occurs causing the athlete to change direction.
The goal of plyometric training is to maximise the stretch shortening cycle of the muscles whilst also strengthening the tendons and ligaments in order that the athlete can better withstand the impact forces of running, jumping and changing direction, increase power output (and therefore improve speed) and reduce the risk of injury.
Plyometric training can add a fun and challenging component for athletes but due to the very nature of the potentially high impact forces involved needs to be introduced and coached gradually into a programme.
Low intensity movements involving limited complexity and low impact forces should form the basis of the initial programme. Then after a period of time when technique is proficient and slow movements are done correctly the impact forces and / or movement complexity can be increased, and instability introduced (ie depth box jumps on one leg as opposed to two legs).
Some of the more recognised benefits of plyometric training are: increased jump height and length, strength, running speed, throwing ability and reduced likelihood of injury.
CAUTION: By their very nature, unilateral and gravity accelerated movements such as bounding, hops, depth jumps and combination jumps require a good level of stability, motor control, coordination, eccentric strength, joint stability and technical proficiency to avoid injury.
So go jump and have fun.