The spectrum analysis of the electromyogram: the adaptation of autoregressive models to the interference electromyogram]

Power-density spectra of interference electromyograms of M. biceps brach. and triceps brach. from two subjects were estimated by the Tukey spectral window and by autoregressive series. By fitting autoregressive models parametric represeentations of spectra are obtained. The models for the electromyograms obtained from biceps (agonist) and triceps (antagonist) differed in the length of the autoregressive series. The intra-individual variation of the spectra from three time intervals of the same contraction was relatively small.