拮抗肌对的协同控制与EMG信号的中值频率关系

探讨在持续恒力收缩时,正常人体肘关节主动肌和桔抗肌的协同作用原理与它们的表面EMG信号中值频率(Median Frequency,MF)的变化趋势,研究它们的疲劳行为。十五个正常受试者的实验数据统计结果表明,拮抗肌的SEMG/MF高于主动肌;随着收缩时间的增加,主动肌和拮抗肌的MF几乎以相同的速率下降;收缩力越大,它们的两条拟合直线之间的距离、互相关系数、下降速率也越大;关节的角度的变化对上述结论似乎没有明显的影响。这些结论对屈曲和伸展模式都成立。利用人体组织的幅度衰减特性和频率衰减特性,神经肌肉系统的“共驱动”概念对上述结果进行了讨论。

The Relations Between the Coactivation of the Elbow Antagonist Muscles and their EMG Median Frequencies

The relationships between the coactivation of the elbow antagonist muscles and their surface Electromyogram (SEMG) Median Frequencies (MFs), as well as the fatigue behaviour have been investigated in this project. The experimental data of 15 normal subjects show that the SEMG/MF of the antagonist is higher than that of the agonist, the MFs of both agonist and antagonist decrease with a similar rate during sustained contraction. The higher the contraction level, the larger the distance and the crosscorrelation coefficients of two regression lines, the faster the decreasing rate. These conclusions are tenable for both extension flexion models. The joint angles seem to affect these conclusions non-significantly. The amplitude and frequency decrement functions of the tissues have been used to discuss the results.