Fig. 6.

Correlation between the soleus locomotor background EMG and H-reflex (a) or M1 stretch reflex size (b) and correlation between H-reflex size and M1, M2, or M3 stretch reflex size (c). a Mean rectified H-reflex sizes from 8 bins of the step cycle are plotted against background EMG (i.e., control EMG of non-stimulated steps for the period corresponding to the time of reflex elicitation) in a representative participant with SCI (blue crosses) and a participant without SCI (black circles). Coefficient of determination r² values and the corresponding regression lines are also indicated in blue (participant with SCI) and black (participant without SCI). b Mean rectified M1 reflex sizes from eight bins of the step cycle are plotted against background (control) EMG in the same representative individuals as in a. c Pearson’s correlation coefficient r value is calculated for each of the 8 bins of the step cycle for each group. Light red bands indicate statistically significant (p < 0.05) r value ranges