MacDougall J D, Sale D G, Elder G C, Sutton J R
Eur J Appl Physiol Occup Physiol. 1982;48(1):117-26. doi: 10.1007/BF00421171.
Muscle ultrastructure of a group of subjects possessing extreme hypertrophy was compared with that of a control group which had undergone 6 months of heavy resistance training. Two needle biopsies were taken from triceps brachii of two international calibre powerlifters and five elite bodybuilders. In addition, samples were taken from five healthy volunteers before and after 6 months of training of the elbow extensors. One biopsy was prepared for electron microscopy and analyzed stereologically, and the other was stained for myosin ATPase activity and photographed under the light microscope. Despite large differences in elbow extension strength and arm girth there was no significant difference in fibre areas or percentages of fibre types between the elite group and the trained controls. This suggests that the elite group possessed a greater total number of muscle fibres than the controls did. Mitochondrial volume density of the elite group was similar to that of the control group following training but significantly less (p less than 0.05) than the pretraining control measurements. Myofibrillar volume density was significantly lower and cytoplasmic volume density significantly higher in the elite group than in the trained controls. There was a considerably higher incidence of structural abnormalities including central nuclei and atrophied fibres in the elite group than in the control group, which might possibly have been associated with the use of anabolic steroids by the elite group.
将一组具有极度肌肉肥大的受试者的肌肉超微结构与经过6个月大强度抗阻训练的对照组进行了比较。从两名国际水平的力量举运动员和五名精英健美运动员的肱三头肌处采集了两次针吸活检样本。此外，还从五名健康志愿者的肘部伸肌训练前和训练6个月后采集了样本。一份活检样本用于电子显微镜检查并进行体视学分析，另一份则进行肌球蛋白ATP酶活性染色并在光学显微镜下拍照。尽管精英组和训练对照组在肘部伸展力量和上臂围度上存在很大差异，但在纤维面积或纤维类型百分比方面没有显著差异。这表明精英组的肌纤维总数比对照组更多。精英组的线粒体体积密度在训练后与对照组相似，但显著低于训练前对照组的测量值（p小于0.05）。精英组的肌原纤维体积密度显著低于训练对照组，而细胞质体积密度显著高于训练对照组。精英组中包括中央核和萎缩纤维在内的结构异常发生率比对照组高得多，这可能与精英组使用合成代谢类固醇有关。
