Wang Du-ming, Wang Jian, Ge Lie-zhong
Psychology Department, Zhejiang University, Hang-Zhou, China.
Space Med Med Eng (Beijing). 2004 Jun;17(3):201-4.
To investigate the numerical relationship between the changes of surface electromyographic (sEMG) signal indexes and subjective assessment of muscle fatigue during isometric contractions.
Eleven healthy subjects participated in the experiment. The sEMG signals of biceps were recorded during their sustained isometric contractions at 50% maximum voluntary contraction (MVC). Fatigue was subjectively rated using a Borg CR-10 scale. Correlations between Borg ratings and a series of fatigue-related indexes such as MPF, MF and Lempel-ziv complexity were analyzed, and curve estimation was also explored.
A strong positive correlation was found between Borg ratings and endurance time, and negative correlations at different degrees were found between Borg ratings and each of sEMG signal indexes. Curve estimation (Logarithmic curve and Power curve) was also significant.
The significant correlation between the Borg scale, sEMG signal indexes and endurance time indicates a close relationship between subjective and objective assessment of muscle fatigue. The numerical relationship between them accord with the power law of Stevens in psychophysics relatively.
研究等长收缩过程中表面肌电图(sEMG)信号指标变化与肌肉疲劳主观评估之间的数值关系。
11名健康受试者参与实验。在他们以最大自主收缩(MVC)的50%进行持续等长收缩时,记录肱二头肌的sEMG信号。使用Borg CR - 10量表对疲劳进行主观评分。分析Borg评分与一系列疲劳相关指标(如平均功率频率(MPF)、中值频率(MF)和Lempel - ziv复杂度)之间的相关性,并进行曲线估计。
发现Borg评分与耐力时间之间存在强正相关,且Borg评分与每个sEMG信号指标之间存在不同程度的负相关。曲线估计(对数曲线和幂曲线)也具有显著性。
Borg量表、sEMG信号指标与耐力时间之间的显著相关性表明肌肉疲劳主观评估与客观评估之间存在密切关系。它们之间的数值关系相对符合心理物理学中史蒂文斯的幂定律。