Department of Biomedical Engineering, Cleveland Clinic Foundation, Cleveland, OH 44195-5254, U.S.A.
J Electromyogr Kinesiol. 1995 Sep;5(3):141-9. doi: 10.1016/1050-6411(95)00010-w.
Muscle fatigue can be caused by a number of different mechanisms that result in an acute reduction in the ability to perform a motor task. These mechanisms include the physiological processes that range from the motivation associated with performing the task through to the force exerted by the contractile proteins once they are activated. Two issues are examined in this brief review. First, the role of mechanisms located in the central nervous system (central factors) in the fatigue experienced by human subjects. Second, the importance of task conditions (task dependency) on the fatigue mechanisms involved in a particular performance. The literature documents a prominent role for central factors in the development of muscle fatigue. This role is examined by considering subject motivation, the descending signals sent by suprasegmental centres (central command) and motor unit behaviour. The significance of these or other mechanisms, however, appears to depend on the details of the task. Variation in such requirements as contraction intensity or duration, speed of movement, or type of muscle contraction alters the role of the different mechanisms in limiting performance. Unfortunately, few studies have examined these effects systematically. The field of muscle fatigue would benefit substantially from studies that determined the boundary conditions for the different fatigue mechanisms.
肌肉疲劳可能由多种不同的机制引起，这些机制导致运动任务的能力急性下降。这些机制包括从与执行任务相关的生理过程到收缩蛋白一旦被激活所产生的力的范围。本综述探讨了两个问题。首先，位于中枢神经系统（中枢因素）中的机制在人体受试者经历的疲劳中的作用。其次，特定性能涉及的疲劳机制对任务条件（任务依赖性）的重要性。文献记录了中枢因素在肌肉疲劳发展中的突出作用。通过考虑受试者的动机、超节段中心发出的下行信号（中枢命令）和运动单位行为来研究这一作用。然而，这些或其他机制的重要性似乎取决于任务的细节。收缩强度或持续时间、运动速度或肌肉收缩类型等要求的变化改变了不同机制在限制性能方面的作用。不幸的是，很少有研究系统地检查这些影响。肌肉疲劳领域将从确定不同疲劳机制的边界条件的研究中受益匪浅。
