[Study on mechanical factors involved in sports muscle injury].

Objective. To investigate the effect of eccentric strengthening (EC) exercise on muscular structure, plasma CK and biomechanical behavior under different mechanical loadings and to study the mechanical factors involved in sports muscle injury. Method. We developed an apparatus to do eccentric strength training with male SD rats under different mechanical loadings and to measure the biomechanical behavior. Result. No significant difference (P>0.05) of muscular structure, plasma CK and biomechanical behavior were found between high and low force groups. Conclusion. Skeletal muscle injury after cyclic EC with different mechanical loadings suggested that muscle damage is not simply a function of peak muscle force.