Effects of low and high frequency transcutaneous electrical nerve stimulation on the intensity and threshold of pain during the stretching of hamstring muscle

authors:

avatar Hamid Reza Bokayyan , avatar Amir Hoshang Bakhtiary , * , avatar Mohammad Ardestani , avatar Milad Iravani

Koomesh: Vol.16, issue 1; 23-28
published online: October 28, 2014
article type: Research Article
received: August 02, 2013
accepted: May 02, 2014

how to cite: Bokayyan H R, Bakhtiary A H, Ardestani M, Iravani M. Effects of low and high frequency transcutaneous electrical nerve stimulation on the intensity and threshold of pain during the stretching of hamstring muscle. koomesh. 2014;16(1):e151276. 

Abstract

 Introduction: Transcutaneous electrical nerve stimulation (TENS) has been very useful in controlling various pains such of muscle stretching pain. In this study, we investigated the effects of high and low frequency TENS on pain reduction during muscle stretching. Materials and Methods: 60 male students with tight hamstrings were assessed and randomly assigned into one of the three experimental groups (n = 20 in each group): 1) high TENS, 2) low TENS, 3) and control. In the first session all groups received static hamstring stretching exercise technique, while both experimental groups received combined stretching exercises and TENS in the second session (one week later). The control group received only stretching exercises. During both sessions, pain was measured by VAS and pain threshold was evaluated by goniometer. Results: Pain threshold increased significantly (P=0.001) in low TENS group, whereas the high TENS and control groups showed no significant increase. All experimental groups failed to show any significant changes in pain intensity. Conclusion: The results of this study showed that low-frequency TENS may increase the pain threshold during static stretching of the hamstring muscle. These findings may indicate the clinical value of low-TENS to perform static stretching techniques on hamstring muscles tightness