耐力训练对骨骼肌纤维类型和超微结构的影响

本研究通过对大白鼠长期的耐力训练,观察其对大白鼠骨骼肌纤维类型及肌中线粒体体密度的不同影响,认为对以慢肌纤维为主的比目鱼肌影响不大,对以快肌纤维为主的趾长伸肌有明显的影响,对其肌中的线粒体体密度的增加有显著意义。

THE INFLUENCES OF ENDURANCE TRAINING UPON THE TYPES OF SKELETAL MUSCLE FIBERS AND FIBER ULTRASTRUCTURES

Different influences of long-term endurance training in swimming can be obtained upon the types of skeletal muscle fibers of the white rats. The influence on the muscles soleus is minor, while that of m. extensor digitorum longus is obvious, with slow muscle fibers rising from the original 50.60% to 76.4%.There are marked influences of long-term endurance training upon the ultrastructures of skeletal muscles. The training has very great significance for the volume density increase of the mitochondria of m. extensor digitorum longus. There are only slight influences on the width of Z hands and the volume density of T tubules, and the volume density of lipid droplets are greatly reduced. This shows that the long-term endurance training has changed the metabolic types of muscle fibers.Following the increase of time for endurance training, the electrons in mitochondria will change from dense to transparency: the cristae will break or even appear in the form of vacuoles; Z bands will become wavy and a part of the sarcomeres will vanish.