ABSTRACT
In studies of the spinal circuits, change of Renshaw cell activity is measured by H_ response. For recording H' response, new electrical stimulation device was designed and built; and the first recorded H' response in Iran was done. The purpose of this study was to investigate the intersession and intra-session reliability of peak amplitude of H' response and its related intensity detected of new device. Soleus muscles of dominant extremity in 6 subjects were tested in 3 sessions and 2 times in each session that intra-session interval was 20 minutes and intersession interval was 1 week. Peak amplitude and its related intensity exhibited intra-session and intersession reliability 0.92, 0.98, 0.86 and 0.9 respectively. Standard Error of Measurement was 0.37 and 0.47 for intra-session and 0.44 and 1.06 for inter session respectively. Peak amplitude and its related intensity exhibited very high intra-session and intersession reliability