Effect of Extracorporeal Shock Wave Therapy on Hamstring Tightness in Healthy Subjects: A Pilot Study

Purpose: To assess the effect of extracorporeal shock wave therapy (ESWT) for healthy participants with hamstring tightness. Materials and Methods: This study was performed at a university rehabilitation hospital. Twenty nine healthy adults with hamstring tightness were enrolled and randomly allocated into four groups (ESWT, stretching exercise, ESWT with stretching exercise, and control). The effects of individual treatments were compared by the finger-to-floor test and popliteal angle. Results: The ESWT group, stretching exercise group and ESWT with stretching exercise group had decreased finger-to-floor distances and right popliteal angles immediately after intervention, compared with the control group (p<0.05). At 4 weeks after completion of the interventions, finger-to-floor distances and the right popliteal angle in only the ESWT with stretching exercise group showed a significant improvement, compared with the control group (p=0.008 and 0.023). Conclusion: While ESWT and stretching both reduced hamstring tightness immediately after interventions, only ESWT with stretching exercise maintained the significantly improved relief of hamstring tightness significantly after 4 weeks.