Abstract
The purpose of this study was to quantify changes in Renshaw cell activity from supine to standing and determine the relationship between these changes and changes in the soleus H-reflex. Ten young subjects were tested using an indirect measure of Renshaw cell activity. Twelve test and twelve conditioned H-reflexes were collected during both supine and standing conditions. All subjects significantly increased Renshaw cell activity from supine to standing. Furthermore, there was a significant correlation between the changes in H-reflex and Renshaw cell activity. As the co-contraction requirement of the system increased, Renshaw cell activity also increased.