Hagberg M
Eur J Appl Physiol Occup Physiol. 1979 Mar 1;40(4):265-72. doi: 10.1007/BF00421518.
A measure of the variation of load on individual muscles or parts of muscles may be obtained by estimating the amplitude probability distribution function (APDF) of the myoelectric signal. In a study of elbow flexor muscular performance in static and intermittent static low level muscular contractions, the APDF was computed from the surface EMG obtained from the belly of the brachial biceps muscle. The APDF was also computed from the simultaneously recorded force signal. The APDF of the myoelectric signal and of the force signal were similar, indicating that the APDF of the myoelectric signal closely reflects the muscular load in non-fatiguing muscular contractions. The effect of the time constant in lowpass filtering when processing the surface EMG-signals was also studied. A suitable time constant appears to be in the range of 50-100 ms.
通过估计肌电信号的幅度概率分布函数（APDF），可以获得单个肌肉或肌肉部分负荷变化的一种度量。在一项关于静态和间歇性静态低水平肌肉收缩时肘部屈肌肌肉性能的研究中，APDF是根据从肱二头肌肌腹获取的表面肌电图计算得出的。APDF也是根据同时记录的力信号计算得出的。肌电信号和力信号的APDF相似，这表明在非疲劳性肌肉收缩中，肌电信号的APDF能密切反映肌肉负荷。还研究了处理表面肌电信号时低通滤波中时间常数的影响。合适的时间常数似乎在50 - 100毫秒范围内。
