Peripheral and extra torques generated by stimulation pattern 1. A) Schematic representation of stimulation pattern 1 showing the time course of alternating 2-s of 20-Hz and 100-Hz bursts of electrical stimulation. B) Average plantarflexion torque as a function of time (n = 8, thick line) with SD shown in light shade. Bars (thin line) represent the values of peripheral torque (PT) and extra torques (ETs, means ± SDs). Note that the ET values are the increments with respect to the PT value. The eight extra torque values generated by the series of 100-Hz bursts are labeled ET1 -- ET8. Data are from a representative subject. D) Average extra torques (± SEMs) representing group data (n = 48). Asterisks indicate extra torque values significantly different from zero (p < 0.05).