Enoka R M, Stuart D G
Department of Physiology, University of Arizona, Tucson 85721.
J Appl Physiol (1985). 1992 May;72(5):1631-48. doi: 10.1152/jappl.1992.72.5.1631.
Muscle fatigue encompasses a class of acute effects that impair motor performance. The mechanisms that can produce fatigue involve all elements of the motor system, from a failure of the formulation of the descending drive provided by suprasegmental centers to a reduction in the activity of the contractile proteins. We propose four themes that provide a basis for the systematic evaluation of the neural and neuromuscular fatigue mechanisms: 1) task dependency to identify the conditions that activate the various mechanisms; 2) force-fatigability relationship to explore the interaction between the mechanisms that results in a hyperbolic relationship between force and endurance time; 3) muscle wisdom to examine the association among a concurrent decline in force, relaxation rate, and motor neuron discharge that results in an optimization of force; and 4) sense of effort to determine the role of effort in the impairment of performance. On the basis of this perspective with an emphasis on neural mechanisms, we suggest a number of experiments to advance our understanding of the neurobiology of muscle fatigue.
肌肉疲劳包括一类损害运动表现的急性效应。能够产生疲劳的机制涉及运动系统的所有要素，从节段上中枢提供的下行驱动信号形成失败到收缩蛋白活性降低。我们提出四个主题，为系统评估神经和神经肌肉疲劳机制提供基础：1）任务依赖性，以确定激活各种机制的条件；2）力量-疲劳性的关系，以探索导致力量与耐力时间呈双曲线关系的机制之间的相互作用；3）肌肉智慧，以研究力量、放松速率和运动神经元放电同时下降之间的关联，这种关联会导致力量优化；4）努力感，以确定努力在表现受损中的作用。基于这种强调神经机制的观点，我们建议进行一些实验，以增进我们对肌肉疲劳神经生物学的理解。
