Plyometric Training

Plyometric training is a form of exercise built around rapid stretch-shortening cycles, in which an active muscle-tendon unit is lengthened and then quickly transitions into shortening. Common plyometric movements include jumping, hopping, bounding, and other explosive actions in which force is produced rapidly .^1,2

During a stretch-shortening cycle, the initial lengthening phase involves eccentric muscle action, while the subsequent shortening phase involves concentric muscle action. Performing these phases in rapid succession can enhance force, work, or power during the shortening phase compared with a similar shortening action performed without the preceding stretch .²

Several mechanisms contribute to this effect. Elastic tissues, particularly tendons, can store mechanical energy during the lengthening phase and return some of it during the subsequent shortening phase. Muscle preactivation, stretch-related neural responses, and history-dependent mechanical properties of muscle can also contribute. Their relative importance varies with factors such as movement speed, loading, and the time between lengthening and shortening .^1,2

Plyometric training is defined by the use of rapid stretch-shortening cycles rather than simply by performing jumps. Although many plyometric programs use jumping exercises, the broader concept can include upper- or lower-body movements that rapidly couple a preparatory stretch with an explosive action. Repeated plyometric training can improve qualities such as muscle power and performance in jumping, sprinting, and rapid changes of direction .¹