Behm D G, St-Pierre D M
School of Physical and Occupational Therapy, McGill University, Montreal, Quebec, Canada.
Sports Med. 1998 Mar;25(3):173-89. doi: 10.2165/00007256-199825030-00004.
Increases in force, electromyography, reflex potentiation, muscle action potential amplitude and protein synthesis occur with strength training. Training-induced increases in the efficiency of the neuromuscular system and capacity of the muscle to generate force result in an improved ability to cope with a submaximal load. There is also some evidence of improved fatigue resistance with maximal contractions which could be attributed to a prolongation of membrane excitation or decreased antagonist activity with training. On the other hand, although a variety of factors including strength are diminished with disuse, a number of studies have demonstrated no significant difference in the rate of fatigue with maximal contractions (fatigue index) between trained, untrained and disused muscle. Equivalent control and disuse fatigue indexes in some studies might be attributed to decreased muscle activation resulting in a comparison of maximal (control) and submaximal (disuse) efforts. Furthermore, increases in the duration of muscle membrane electrical propagation with disuse may increase the quantity of Ca++ released, augmenting force production. In addition, the smaller volume of disused muscle may allow a more efficient diffusion of oxygen and energy substrates in comparison with a hypertrophied muscle.
力量训练会使力量、肌电图、反射增强、肌肉动作电位幅度和蛋白质合成增加。训练引起的神经肌肉系统效率提高以及肌肉产生力量的能力增强，会导致应对次最大负荷的能力得到改善。也有一些证据表明，最大收缩时的抗疲劳能力有所提高，这可能归因于膜兴奋的延长或训练导致的拮抗肌活动减少。另一方面，尽管包括力量在内的多种因素会因废用而减弱，但多项研究表明，训练过的肌肉、未训练的肌肉和废用肌肉在最大收缩时的疲劳率（疲劳指数）并无显著差异。一些研究中对照组和废用组的疲劳指数相当，可能是由于肌肉激活减少，导致最大（对照组）和次最大（废用组）努力程度的比较。此外，废用会增加肌肉膜电传播的持续时间，可能会增加钙离子的释放量，从而增强力量产生。此外，与肥大的肌肉相比，废用肌肉体积较小，可能使氧气和能量底物的扩散更有效。
