The Immediate Effect of Static and Dynamic Stretching on Flexibility of Hamstring, Dynamic Balance Ability, Function of Lower Extremity: Randomized Controlled Trial

Abstract

Purpose: This study examined the acute effects of static and dynamic stretching on the flexibility of the hamstring, dynamic balance ability, and function of the lower extremities in healthy adults. Methods: Thirty participants were assigned randomly to three groups: static stretching group (SSG), basic dynamic stretching group (BDSG), and 5 sec dynamic stretching group (5DSG). SSG performed three sets of 30 seconds of static stretching. BDSG performed a sin- gle-leg deadlift (SLD) at the same time as SSG, and 5DSG performed SLD held for five seconds. Hamstring flexibility, dynamic balance ability, and lower extremity function were evaluated before and after intervention. Results: The hamstring flexibility significantly improved in all groups (p < 0.05). The dynamic balance ability improved significantly after in- tervention in all groups except BDSG in the anterior direction (p < 0.05). There were significant differences in the posterolateral and pos- teromedial direction in all groups. The function of the lower extremity showed significant improvement over time only in BDSG (p < 0.05). Conclusion: This study suggested that basic dynamic stretching and 5 sec dynamic stretching positively affect the hamstring flexibility, dynamic balance ability, and lower extremity function. Therefore, it is recommended to include dynamic stretching in a program for im- proving the hamstring flexibility, dynamic balance ability, and the lower extremity function. In addition, it is recommended to apply it at different times depending on the purpose.