The Exercise Myopathy

Abstract

Summary: It seems that there is some similarity between the structural changes in fast-glycolytic and fast-oxidative-glycolytic muscle fibers in case of exercise myopathy, although destructive changes in the glycolytic muscle fibers seem to be of smaller scope. On the one hand, this can be explained by the fact that glycolytic fibers do not participate so actively in the low-intensive exercise. On the other hand, the fairly large range of destructive processes in these fibers shows that glycolytic muscle fibers participate in long-term low-intensive exercise performing the junction of the skeletal muscle in the role of an organ. It is well known, that fast-twitch muscle fibers are more sensitive to the action of corticosteroids. Therefore it is probable that the increase of endogenous corticosteron level in endurance-type exhausted rats and cortisol level in overtrained athletes may be the important factor in the pathogeneses of the exercise myopathy.