Department of Integrative Physiology, University of Colorado, Boulder, Colorado 80309-0354.
Laboratory of Applied Biology and Neurophysiology, Neuroscience Institute, Université Libre de Bruxelles, 1070 Brussels, Belgium.
Cold Spring Harb Perspect Med. 2017 Oct 3;7(10):a029702. doi: 10.1101/cshperspect.a029702.
The force exerted by a muscle during a voluntary contraction depends on the number of motor units recruited for the action and the rates at which they discharge action potentials (rate coding). Over most of the operating range of a muscle, the nervous system controls muscle force by varying both motor unit recruitment and rate coding. Except at relatively low forces, however, the control of muscle force depends primarily on rate coding, especially during fast contractions. This review provides five examples of how the modulation of rate coding influences the force exerted by muscle during voluntary actions. The five examples comprise fast contractions, lengthening and shortening contractions, steady isometric contractions, fatiguing contractions, and contractions performed after a change in the daily level of physical activity.
肌肉在进行随意收缩时所产生的力取决于参与该动作的运动单位数量以及它们发放动作电位的速率（速率编码）。在肌肉的大部分工作范围内，神经系统通过改变运动单位募集和速率编码来控制肌肉力量。然而，除了相对较低的力之外，肌肉力量的控制主要取决于速率编码，尤其是在快速收缩期间。本综述提供了五个例子，说明速率编码的调制如何影响肌肉在随意运动中所产生的力。这五个例子包括快速收缩、拉长和缩短收缩、稳态等长收缩、疲劳收缩以及在日常体力活动水平改变后进行的收缩。
