Jackson C G, Dickinson A L, Ringel S P
Department of Kinesiology, University of Northern Colorado, Greeley 80639.
Eur J Appl Physiol Occup Physiol. 1990;61(1-2):37-41. doi: 10.1007/BF00236691.
The purpose of this study was to observe fiber area changes that might occur in the same subject from two opposing resistance-exercise training regimes isolating the quadriceps muscle group. Twelve college-age men divided into two groups participated in each of two 7.5-week regimens; one performed a muscular strength program (high-resistance, low-repetition) 4 days a week on a resistance-exercise apparatus, while the other performed a muscular endurance (low-resistance, high-repetition) program. After a 5.5-week hiatus, the groups changed regimens for the second 7.5 weeks. Closed-needle biopsies of the dominant vastus lateralis and isokinetic dynamometer evaluations were made before and at the end of each training period. The muscle samples were analyzed for area changes. In both groups the initial exercise stimulus, whether for strength or endurance, increased the area of fibers of all three major types (I, IIA, and IIB). Subjects doing strength exercises as their second treatment showed a further increase in the area of type I and IIB fibers, whereas those doing endurance exercises showed a decrease in all fiber types. From the first to the last biopsy all fiber areas were decreased (P less than 0.05) in the control-strength-endurance group and increased (P less than 0.05) in the control-endurance-strength group. These results suggested that endurance exercise preceding strength exercise in an isolated muscle group maximized fiber area adaptations to exercise stress. Consideration should thus be given in exercise and rehabilitation programs to the muscle cellular adaptations evidenced in different orders of training, particularly if muscular strength is considered important.
本研究的目的是观察在同一个体中，针对股四头肌群的两种相反的抗阻训练方案可能导致的纤维面积变化。12名大学年龄男性被分为两组，每组参与两个7.5周的训练方案；一组每周4天在抗阻训练器械上进行肌肉力量训练（高阻力、低重复次数），另一组进行肌肉耐力训练（低阻力、高重复次数）。经过5.5周的间歇期后，两组在第二个7.5周改变训练方案。在每个训练期开始前和结束时，对优势股外侧肌进行闭合针活检，并进行等速测力计评估。对肌肉样本进行纤维面积变化分析。在两组中，无论是力量训练还是耐力训练，初始运动刺激都增加了所有三种主要纤维类型（I型、IIA型和IIB型）的纤维面积。作为第二种训练进行力量训练的受试者，I型和IIB型纤维面积进一步增加，而进行耐力训练的受试者所有纤维类型的面积均减少。从第一次活检到最后一次活检，在力量-耐力对照组中所有纤维面积均减少（P<0.05），在耐力-力量对照组中所有纤维面积均增加（P<0.05）。这些结果表明，在孤立的肌肉群中，先进行耐力训练再进行力量训练能使纤维面积对运动应激的适应性最大化。因此，在运动和康复计划中，应考虑不同训练顺序下肌肉细胞的适应性，特别是在认为肌肉力量很重要的情况下。
