Costill D L, Coyle E F, Fink W F, Lesmes G R, Witzmann F A
J Appl Physiol Respir Environ Exerc Physiol. 1979 Jan;46(1):96-9. doi: 10.1152/jappl.1979.46.1.96.
Five men were studied before and after 7 wk of isokinetic strength training to determine its effects on muscle enzyme activities and fiber composition. One of the subject's legs was trained using 10 repeated 6-s maximal work bouts, while the other leg performed repeated 30-s maximal knee extension exercise. The total work accomplished by each leg was constant. Training 4 times/wk achieved similar gains in peak torque for both legs at the training velocity (3.14 rad/s) and at slower speeds. Fatigability of the knee extensor muscles, as measured by a 60-s exercise test, was similar in both legs after training. Biopsy specimens showed significant changes in the % of the muscle area composed of type I and IIa fibers as a result of both strength training programs. In terms of muscle enzymes, only the 30 s exercise program resulted in elevated glycolytic, ATP-CP and mitochondrial activities. Despite these changes, none of the parameters measured were found to be related to the gains in either muscle strength or fatigability during maximal isokinetic contractions.
对五名男性进行了研究，观察他们在进行7周等速力量训练前后的情况，以确定该训练对肌肉酶活性和纤维组成的影响。其中一名受试者的一条腿进行10组持续6秒的最大强度训练，另一条腿进行重复30秒的最大强度伸膝运动。每条腿完成的总工作量是恒定的。每周训练4次，在训练速度（3.14弧度/秒）和较慢速度下，两条腿的峰值扭矩都有相似的增加。通过60秒运动测试衡量，训练后两条腿的膝伸肌疲劳程度相似。活检标本显示，两种力量训练方案均导致由I型和IIa型纤维组成的肌肉面积百分比发生显著变化。在肌肉酶方面，只有30秒运动方案导致糖酵解、ATP - CP和线粒体活性升高。尽管有这些变化，但在最大等速收缩过程中，所测量的参数均未发现与肌肉力量或疲劳程度的增加有关。
