Effects of femoral nerve stimulation on soleus voluntary EMG activity in 13 stroke and 10 healthy participants. Mean modulation of soleus voluntary EMG activity induced by FN stimulation for the stroke group (black squares) and the control group (white squares) expressed as a percentage of unconditioned EMG. Modulations are presented within the four time windows from 0 to 6 ms, 12 to 24 ms, 24 to 36 ms and 36 to 48 ms after the zero of central delay. Positive values (i.e., above zero on the ordinate scale) are facilitation and negative values are inhibition. Vertical bars =1 SEM. Asterisks represent significant differences in modulation between the control and stroke participants (* p ≤0.05; ** p ≤0.01; *** p ≤0.001).