Hof A L, Pronk C N, van Best J A
J Biomech. 1987;20(2):167-78. doi: 10.1016/0021-9290(87)90308-3.
In EMG to force processing the force of a muscle or the corresponding muscle moment with respect to the joint is determined from EMG and muscle length by means of a model of the muscle's contractile and elastic properties. In kinetic analysis the joint moment is calculated from the ground reaction force and the positions and accelerations of the body segments by means of Newtonian equations, based on a rigid body segment model. These two fundamentally different methods have been compared by determining simultaneously the calf muscle moment and the total ankle moment in walking at slow, moderate and fast speed and in stepping up and down a low bench. As long as there is no activity of other muscles, the moments obtained by either method should be identical. The analysis was restricted to such periods, as assessed from the EMG of tibialis anterior. In each experimental condition three steps were analyzed in five subjects of 21-22 yr. In comparison with the results of kinetic analysis, EMG processing shows differences between 7 and 54 Nm r.m.s., with an average of 22 Nm r.m.s. Normalized with respect to the r.m.s. value of the moment itself, the differences amount to 0.13-0.51, with an average of 0.22. In the majority of cases there was no systematic deviation between EMG processing and kinetic analysis and the r.m.s. difference was of the same order of magnitude as determined previously in ergometer experiments.
在肌电图到力的处理过程中，利用肌肉收缩和弹性特性模型，根据肌电图和肌肉长度确定肌肉的力或相对于关节的相应肌肉力矩。在动力学分析中，基于刚体节段模型，通过牛顿方程从地面反作用力以及身体节段的位置和加速度计算关节力矩。通过在慢、中、快三种步行速度下以及上下一个低长凳时同时确定小腿肌肉力矩和总踝关节力矩，对这两种根本不同的方法进行了比较。只要没有其他肌肉活动，两种方法得到的力矩应该是相同的。根据胫骨前肌的肌电图评估，分析仅限于这样的时间段。在每个实验条件下，对5名21至22岁的受试者的三步进行了分析。与动力学分析结果相比，肌电图处理显示的差异在均方根值7至54 Nm之间，平均为22 Nm均方根值。相对于力矩本身的均方根值进行归一化后，差异为0.13至0.51，平均为0.22。在大多数情况下，肌电图处理和动力学分析之间没有系统偏差，均方根差异与之前在测力计实验中确定的处于同一数量级。
