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

摘要

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 (MMG_(RMS))-force relationships, EMG M-Waves, and MMG gross lateral movements (GLM). Methods: 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 MMG_(RMS)-force relationships, EMG M-waves, and MMG GLMs. Results: There were no significant cor1relations (p >0.05) between the a terms and skinfold thicknesses for the RF and VL from the EMGRMS and MMG_(RMS)-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). Discussion: Relationships were only present between skinfold thickness and the amplitudes of the EMG and MMG signals during the non-voluntary muscle actions.