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Background and Aim: 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.
Materials and Methods: 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.
Results: 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 intrasession and 0.44 and 1.06 for inter session respectively.
Conclusion: Peak amplitude and its related intensity exhibited very high intra-session and intersession reliability.