力量和耐力训练对肌球蛋白重链及肌纤维转型的影响

The Influence of Strength and Endurance on Myosin Heavy Chain and Fiber Type Transitions

利用肌球蛋白重链的特异性单克隆抗体对股四头肌肌肉活检样本进行免疫组化染色以分析肌纤维亚型的转变和肌细胞横截面积的变化,同时用电泳的方法观察肌球蛋白重链含量的变化。结果发现,IID/A混合型肌纤维的比例在力量训练6周和12周后都出现了显著的下降;I/IIA混合型肌纤维的比例在力量训练6周和12周后都出现了显著的上升。电泳分析发现在两个训练组的MHCIId/x含量的比例都在训练12周后出现显著下降。另外,力量训练造成了I和IIA型肌纤维的横截面积在12周后显著增加。因此我们得出,不同训练模式后受试者的肌纤维展示了对训练过程不同的适应模式。

The purpose of this study was to investigate the effect of strength, endurance and combined strength and endurance training on immunohistochemically delineated fiber type transitions, MHC content and fiber cross-sectional areas (CSA) of the lateral aspect of the right vastus lateralis muscle. Twenty seven volunteers were randomly assigned separately to one of three groups: control (C) group (4 males, 4 females), endurance (E) training group (6 males, 5 females), strength (S) training group (6 males, 2 females). The S and E groups each trained 3 times a week for 12 weeks. Physiological testing was performed prior to and after 6 and 12 weeks of training for all training groups. Immunohistochemical analyses using myosin heavy chain isoform specific monoclonal antibodies demonstrated a significant decrease in the percentage of type IID/A mixed fibers after 6 and 12 weeks training in the S group. The percentage of type I/IIA mixed fibers increased significantly after 6 and 12 weeks of S training only. The data from MHC electrophoresis showed that the proportion of MHCIId/x isoform content decreased significantly in all training regimes after 12 weeks. The CSA of type I and type IIA fibers increased significantly after 12 weeks of S training. It is concluded that two training regimes produced a differential impact on the muscle properties in terms of fiber types, MHC content and CSA of muscle fibers.