Mechanomyographic responses are not influenced by the innervation zone for the vastus medialis

Abstract

The purposes of this study were to: (1) compare the power output-related patterns of absolute and normalized mechanomyographic (MMG) amplitude and mean power frequency (MPF) signals across the innervation zone (IZ) during incremental cycle ergometry; and (2) examine the influence of the IZ on the mean MMG amplitude and MPF values. Ten men performed incremental cycle ergometry tests to exhaustion. Surface MMG signals were recorded simultaneously from accelerometer arrangements placed on the vastus medialis over the IZ and proximal and distal to the IZ. The results of polynomial regression indicate that the best-fit model for each site was consistent for each subject for MMG amplitude, but not for MMG MPF. Two-way analyses of variance (ANOVAs) revealed no site × power output interaction (P > 0.05) for absolute and normalized MMG amplitude and MPF values. Our findings demonstrate that the IZ does not influence the MMG signal during dynamic exercise.