Figure 8

Wavelet- vs. Fourier-based estimates of mechanomyographic (MMG) center frequency. Example of the relationships for mechanomyographic (MMG) center frequencies [wavelet center frequency (WCF), mean power frequency (MPF), and median frequency (MDF)] for the biceps brachii muscle of one subject during 50 consecutive maximal concentric isokinetic muscle actions of the forearm flexors at a velocity of 180°·s^-1. The relationships shown are the best-fit regression models for the MMG WCF, MPF, and MDF data. The discrete wavelet transform was used to calculate the MMG WCF values, and the fast Fourier transform was used to obtain the MMG MPF and MDF values.