The medical consequences of operating outside of the normal boundaries of a well tuned musculo-tendinous system are also poorly understood, although clearly recognized in the persistent atrophy experienced in microgravity despite rigorous exercise programs. Muscle force generation is length and velocity sensitive. The process is repetitive in the sense that muscles will always generate force based on their length-tension and forcevelocity properties, causing tendon deformation. The magnitude of tendon deformation will depend on its own mechanical properties such as stress-strain relationship. Stress-strain curves are an extremely important graphical measure of a material’s mechanical properties. Stress is defined by the ratio of tendon force to tendon cross-sectional area, and strain.
