Modulation of Renshaw Cell Activity from Supine to Standing

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.