Bigland-Ritchie B, Thomas C K, Rice C L, Howarth J V, Woods J J
John B. Pierce Laboratory, New Haven, Connecticut 06519.
J Appl Physiol (1985). 1992 Dec;73(6):2457-61. doi: 10.1152/jappl.1992.73.6.2457.
A study was made of motoneuron firing rates and mechanical contractile parameters during maximum voluntary contraction of human hand muscles. A comparison of muscles that had been fatigued after a 60-s maximum voluntary contraction (MVC) with muscles that were cooled by approximately 5 degrees C showed that the contractile properties, in particular the rates of contraction and relaxation, were similarly affected in both conditions. In contrast, the motoneuron firing rate was affected differently by the two treatments. In the case of the fatigued muscles the motoneuron firing rate was reduced by 36%, as was expected from previous studies, but in the case of the cooled muscles, there was no significant change in the motoneuron firing rate. We conclude that the reflex reduction in the motoneuron firing rate seen in the fatigued muscle is not triggered directly by a change in the mechanical properties of the muscle.
对人手部肌肉最大自主收缩过程中的运动神经元放电频率和机械收缩参数进行了研究。将60秒最大自主收缩（MVC）后疲劳的肌肉与冷却约5摄氏度的肌肉进行比较，结果表明，两种情况下收缩特性，特别是收缩和舒张速率，受到的影响相似。相比之下，两种处理对运动神经元放电频率的影响不同。对于疲劳肌肉，运动神经元放电频率如先前研究所预期的那样降低了36%，但对于冷却肌肉，运动神经元放电频率没有显著变化。我们得出结论，疲劳肌肉中运动神经元放电频率的反射性降低并非直接由肌肉机械性能的变化触发。
