Fig. 2. Mean myoelectric intensity spectra for the plantaris muscle (10° 40 cm s^–1) illustrating the partitioning of the stride into 20 equal time windows. The division between stance swing phase is shown by the thick vertical grey line, arrows indicate the division between initial stance (St 1), late stance (St 2), initial swing (Sw 1) and late swing (Sw 2) phases. Data are shown as mean (black line) ± s.e.m. (grey lines).