Wolf E, Blank A, Shochina M, Gonen B
Am J Phys Med. 1984 Jun;63(3):113-21.
The electrophysiological pattern of fatigue of the biceps brachii (BB) muscle before and after bicycle leg exercise (LE), was evaluated in 12 healthy volunteers. In healthy people, the onset of isometric contraction is initiated by smaller motor units with briefer durations and higher spike frequencies. With the progression of contraction and muscular fatigue, electromyographic decrease in frequency and an increased spike duration occur. In our study, these findings were presented in subjects at the Final Value (FV) of electromyography before and after LE. In 8 subjects, the Initial Value (IV) of spike duration was longer after LE and a decrease in the frequency of electromyography was found in 9 of the 12 subjects. The changes in these two parameters at the onset of the BB contraction after LE may be due to the existence of an electrophysiological transfer effect. Eight subjects sustained the isometric BB contraction longer after LE than before LE. This may be explained by a diverting activity or other factors. Venous lactic acid was measured in 7 subjects and showed an increase after LE. No definite correlation between electromyographic changes and lactic acid was found.
在12名健康志愿者中评估了自行车腿部运动（LE）前后肱二头肌（BB）肌肉疲劳的电生理模式。在健康人群中，等长收缩的起始由持续时间较短、峰值频率较高的较小运动单位引发。随着收缩和肌肉疲劳的进展，肌电图频率降低且峰值持续时间增加。在我们的研究中，这些发现出现在LE前后肌电图终值（FV）的受试者中。在8名受试者中，LE后峰值持续时间的初始值（IV）更长，并且在12名受试者中有9名发现肌电图频率降低。LE后BB收缩开始时这两个参数的变化可能是由于存在电生理转移效应。8名受试者在LE后比LE前维持等长BB收缩的时间更长。这可能由转移活动或其他因素来解释。在7名受试者中测量了静脉乳酸，结果显示LE后有所增加。未发现肌电图变化与乳酸之间有明确的相关性。
