Sharpe M H, Miles T S
School of Physiotherapy, University of South Australia, Adelaide.
Exp Brain Res. 1993;94(1):179-82. doi: 10.1007/BF00230480.
Fatigue is often associated with increased clumsiness. One possible explanation for this is that the proprioceptive signals from receptors in and around muscles change during muscle fatigue. Thirteen human subjects were tested for their ability to match the elbow angle of one arm with the contralateral arm, before and after a fatiguing contraction of one arm. Contractile fatigue was induced by a series of maximal voluntary contractions of the elbow flexors of the dominant arm. While fatigue of either the target arm or the matching arm usually changed the ability of individual subjects to match arm position, this effect varied markedly from one subject to another and no consistent pattern was discerned. In particular, there was no reciprocal change when the fatigued arm was the matching arm compared with when the nonfatigued arm was the matching arm. The absence of a consistent reciprocal effect indicates that the fatigue-related changes in the ability to match arm position are not solely due to changes in proprioceptive signals and that central fatigue processes are probably involved.
疲劳常与动作笨拙增加有关。对此一种可能的解释是，肌肉疲劳时，肌肉内部及周围感受器发出的本体感觉信号会发生变化。对13名受试者进行测试，让他们在一侧手臂进行疲劳收缩前后，将一侧手臂的肘角与对侧手臂相匹配。通过对优势侧手臂的屈肘肌进行一系列最大自主收缩来诱发收缩性疲劳。虽然目标手臂或匹配手臂的疲劳通常会改变个体受试者匹配手臂位置的能力，但这种影响在不同受试者之间差异显著，未发现一致的模式。特别是，与非疲劳手臂作为匹配手臂时相比，当疲劳手臂作为匹配手臂时，并没有出现相反的变化。缺乏一致的相反效应表明，与疲劳相关的匹配手臂位置能力的变化并非仅仅由于本体感觉信号的变化，中枢疲劳过程可能也参与其中。
