The effects of body weight on the soleus H-reflex modulation during standing

Objective: We examined how the soleus H-reflex is affected by the changes in limb loading by testing subjects on a body weight support system during standing. Design: Twenty-two healthy subjects (10 males and 12 females) were recruited for this study. The size of the soleus H-reflex was measured in six different limb loading conditions: 100%, 90%, 80%, 70%, 60%, and 50%. One-way repeated measure ANOVA was used (p < 0.05) to compare the H/M ratios among the six different load conditions. Results: The amplitudes of the soleus H-reflex decreased significantly as the amount of body weight load decreased. Conclusions: Findings of this study suggest that the levels of body weight load in pre- and post-test conditions should be consistent when H-reflex testing is adapted as an outcome measure of rehabilitation intervention for patients with central nerve system lesion such as partial body weight supported gait training. (C) 2010 Published by Elsevier Ltd.