Modulation of extra torques at different joint angles for the group of human subjects. Magnitude of the extra torque (torque evoked during second 25 Hz stimulation ÷ torque evoked during first 25 Hz stimulation × 100) for the group, evoked by plantarflexor (n = 9, A) and dorsiflexor (n = 13, B) top hat stimulations. Asterisks indicate significant differences between joint angles (pairwise comparisons with Bonferroni correction). Each bar is the mean ± SE. *p <0.05, **p <0.01, ***p <0.001.