ABSTRACT
The term “work” is used in physiology in the context of static work in a slightly different way from physics, because the shifting occurs only within the muscle with no visible movement outside. The increase in muscular tension is to the result of the work of the contractile muscular fibers which, in the precise case of an isometric contraction in which the muscle cannot change its length, work against the whole of muscular elastic structures. The work is accomplished by the contractile part of the muscle by stretching the elastic part. In order to characterize this work, one must therefore consider the force developed by the muscle during its isometric contraction, the duration of this contraction, and the conditions which guarantee the energy supply in the muscle. The product of the maintained forceis therefore the measurement of static work widely applied in ergonomics.
