Centre for Physical Activity and Nutrition Research, School of Exercise and Nutrition Sciences, Deakin University, Melbourne, Australia.
J Electromyogr Kinesiol. 2012 Feb;22(1):80-7. doi: 10.1016/j.jelekin.2011.09.012. Epub 2011 Oct 21.
Measuring muscle forces in vivo is invasive and consequently indirect methods e.g., electromyography (EMG) are used in estimating muscular force production. The aim of the present paper was to examine what kind of effect the disruption of the physiological signal caused by the innervation zone has in predicting the force/torque output from surface EMG. Twelve men (age 26 (SD ±3)years; height 179 (±6)cm; body mass 73 (±6)kg) volunteered as subjects. They were asked to perform maximal voluntary isometric contraction (MVC) in elbow flexion, and submaximal contractions at 10%, 20%, 30%, 40%, 50% and 75% of the recorded MVC. EMG was measured from biceps brachii muscle with an electrode grid of 5 columns×13 rows. Force-EMG relationships were determined from individual channels and as the global mean value. The relationship was deemed inconsistent if EMG value did not increase in successive force levels. Root mean squared errors were calculated for 3rd order polynomial fits. All subjects had at least one (4-52) inconsistent channel. Two subjects had inconsistent relationship calculated from the global mean. The mean root mean squared error calculated using leave one out method for the fits of the individual channels (0.33±0.17) was higher (P<0.001) than the error for the global mean fit (0.16±0.08). It seems that the disruption of the physiological signal caused by the innervation zone affects the consistency of the force-EMG relationship on single bipolar channel level. Multichannel EMG recordings used for predicting force overcame this disruption.
在体内测量肌肉力量具有侵入性，因此通常使用间接方法，例如肌电图（EMG）来估计肌肉力量的产生。本文的目的是检验神经支配区对生理信号的干扰对表面 EMG 预测力/扭矩输出的影响。12 名男性（年龄 26（SD±3）岁；身高 179（±6）cm；体重 73（±6）kg）自愿作为受试者。要求他们进行最大自主等长收缩（MVC），以及在记录的 MVC 的 10%、20%、30%、40%、50%和 75%的情况下进行次最大收缩。使用 5 列×13 行的电极网格测量肱二头肌的 EMG。从个体通道和整体平均值确定力-EMG 关系。如果 EMG 值在连续的力水平上没有增加，则认为关系不一致。为三阶多项式拟合计算均方根误差。所有受试者至少有一个（4-52）个不一致的通道。两名受试者的整体平均值计算出的关系不一致。使用逐个排除方法拟合个体通道时计算的均方根误差的平均值（0.33±0.17）较高（P<0.001），比整体平均值拟合的误差（0.16±0.08）高。似乎神经支配区对生理信号的干扰会影响单双极通道水平上力-EMG 关系的一致性。用于预测力的多通道 EMG 记录克服了这种干扰。
