Relationships between skinfold thickness and electromyographic and mechanomyographic amplitude recorded during voluntary and non-voluntary muscle actions

• Published in: Journal of electromyography and kinesiology Vol. 24; no. 2; pp. 207 - 213
• Main Authors: Cooper, Michael A., Herda, Trent J., Vardiman, John P., Gallagher, Phillip M., Fry, Andrew C.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.04.2014
• Subjects: Adult; Electrodes; Electromyography; Electromyography - methods; Female; Femoral Nerve; Humans; Isometric Contraction - physiology; Male; Mechanomyography; Muscle, Skeletal - physiology; Physical Medicine and Rehabilitation; Quadriceps Muscle; Signal Processing, Computer-Assisted; Skinfold Thickness; Young Adult; Mechanomyography; Electromyography; Skinfold thickness
• ISSN: 1050-6411; 1873-5711; 1873-5711
• DOI: 10.1016/j.jelekin.2013.12.005

The purpose of this study was to examine possible correlations between skinfold thicknesses and the a terms from the log-transformed electromyographic (EMGRMS) and mechanomyographic amplitude (MMGRMS)-force relationships, EMG M-Waves, and MMG gross lateral movements (GLM). Forty healthy subjects performed a 6-s isometric ramp contraction from 5% to 85% of their maximal voluntary contraction with EMG and MMG sensors placed on the vastus lateralis (VL) and rectus femoris (RF). A single electrical stimulus was applied to the femoral nerve to record the EMG M-waves and MMG GLMs. Skinfold thickness was assessed at the site of each electrode. Pearson’s product correlation coefficients were calculated comparing skinfold thicknesses with the a terms from the log-transformed EMGRMS-and MMGRMS-force relationships, EMG M-waves, and MMG GLMs. There were no significant cor1relations (p>0.05) between the a terms and skinfold thicknesses for the RF and VL from the EMGRMS and MMGRMS-force relationships. However, there were significant correlations (p<0.05) between skinfold thicknesses and the EMG M-waves and MMG GLMs for the RF (r=−0.521, −0.376) and VL (r=−0.479, −0.484). Relationships were only present between skinfold thickness and the amplitudes of the EMG and MMG signals during the non-voluntary muscle actions.