The Role of Elastic Energy

[Guest guest]

The below may be of interest:

The Role of Elastic Energy in Activities with High Force and Power

Requirements: A Brief Review. JM, Flanagan EP.

J Strength Cond Res. 2008 Aug 14. [Epub ahead of print]

The purpose of this article is to

provide strength and conditioning practitioners with an understanding

of the role of elastic energy in activities with high force and power

requirements.

Specifically, the article covers 1) the nature of elasticity and its

application to human participants, 2) the role of elastic energy in

activities requiring a stretch-shorten cycle such as the vertical

jump, 3) the role of muscular stiffness in athletic performance, 4)

the control of muscular stiffness through feedforward and feedback

mechanisms, and 5) factors affecting muscular stiffness.

Finally, practical applications are provided. In this section, it is

suggested that the storage and reuse of elastic energy is optimized

at relatively higher levels of stiffness. Because stiffness decreases

as fatigue ensues as well as with stretching before an event, the

article emphasizes the need for proper preparation phases in a

periodized cycle and the avoidance of long static stretches before

high-force activities. The importance of teaching athletes to

transition from eccentric to concentric movements with minimal time

delays is also proposed due to the finding that time delays appear to

decrease the reuse of elastic energy. In addition to teaching within

the criterion tasks, evidence is provided that minimizing transitions

in plyometric training, a technique demonstrated to increase

musculotendinous stiffness, can optimize power output in explosive

movements.

Finally, evidence is provided that training and teaching programs

designed to optimize muscular stiffness may protect athletes against

sports-related injuries.

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Carruthers

Wakefield, UK