Abstract des Autors

In the sixties the needle biopsy of skeletal muscle tissue was introduced for metabolic studies in humans. Much of information regarding estimation of muscle fiber composition, fiber cross-sectional area, and energy stores in adaptation to various types of both acute and chronic exercises has come from studies where muscle samples were obtained with a needle biopsy. New trends in the use of muscle biopsy are combinations of the method with others, separation of individual muscle fibers from biopsy samples, combined use of muscle biopsy and isotope administration for investigation of protein metabolism or hormone receptors. When training effects are studied with the aid of muscle biopsy it is necessary to take into consideration that the adaptive changes occur mainly in most active muscle, determined by the used exercises. However, these muscles may not be those whose adaptations are crucial in the performance improvement of athletes. Verf.-Referat