Mechanically-induced fatigue testing

In mechanically induced fatigue tests, the stress or strain is oscillated about some mean stress (strain). If the peak or maximum stress is defined by no and the minimum stress by CTu, then the stress ratio is often defined hyR where... 

Soft tissues subjected to repetitive loading, due to their viscoelastic properties, demonstrate creep and load relaxation. The loss of precision, speed, and control of the neuromuscular system induced by fatigue reduces the abihty of muscles to protect the weakened passive structure, which may explaiu many industrial, cHnical, and recreational injury mechanisms. These results further indicate the necessity of relating clinical protocols to the job and show how short-duration maximal isometric testing alone cannot provide the complex functional interaction of strength, endurance, control, and coordination. 

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