The following is purely speculative It has been shown experimentally that transverse compression of skeletal muscle can ,under some circumstances ,cause the force generated by the muscle during contraction to be reduced (1) . It seems reasonable to think that if the more superficial parts of a muscle such as the pectoralis major contract to apply a force then the deeper fibers of the muscle will be subject to transversal loading .
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Hydraulically discrete fascicles in skeletal muscle