Pease William S, Elinski Michael A
Ohio State University, College of Medicine and Public Health, USA.
Electromyogr Clin Neurophysiol. 2003 Jul-Aug;43(5):267-71.
Electromyographic (EMG) signals are routinely recorded during assessments of biomechanic activity for ergonomic and medical purposes. Surface and intramuscular electrodes (i.m.) are employed by different researchers and there is a continuing need to understand the indications for each. This research evaluated the reproducibility of the shift of the frequency content of the EMG signals during fatiguing exercise using simultaneous recording with these two electrode types. Using healthy adult volunteers, EMG recordings from the vastus lateralis (VL) and anterior tibial (AT) were made during repeated isokinetic exertions causing fatigue. The median power frequency (MPF) was calculated for a 0.5 sec sample of data taken during each concentric contraction. Test-retest, and multiple day repeat testing were performed to exclude the effects of training and fatigue upon the data. Surface electrode recordings demonstrated better reliability testing with values of 0.54 for VL and 0.68 for AT, while simultaneous i.m. recordings were -0.90 and 0.47, respectively. This finding of greater reliability, combined with the ease of use of surface electrodes suggest that they should be preferred for most studies of EMG analysis of muscle fatigue.
在出于人体工程学和医学目的进行生物力学活动评估时，通常会记录肌电图（EMG）信号。不同的研究人员会使用表面电极和肌内电极（i.m.），并且持续需要了解每种电极的适用情况。本研究使用这两种电极类型同时记录，评估了疲劳运动期间EMG信号频率成分变化的可重复性。使用健康成年志愿者，在重复等速运动导致疲劳的过程中，对股外侧肌（VL）和胫前肌（AT）进行EMG记录。在每次向心收缩期间，对0.5秒的数据样本计算中位功率频率（MPF）。进行了重测以及多天重复测试，以排除训练和疲劳对数据的影响。表面电极记录显示出更好的可靠性测试结果，VL的值为0.54，AT的值为0.68，而同时进行的肌内电极记录分别为-0.90和0.47。这种更高可靠性的发现，再加上表面电极使用方便，表明在大多数肌肉疲劳的EMG分析研究中，表面电极应是首选。
