The objective of this study was to examine the effects of two different stretching techniques on range of motion (ROM), muscle activation, and balance. For this study, 48 adults with hamstring muscle tightness were recruited and randomly divided into three groups: a static stretching group (n=16), a PNF stretching group (n=16), a control group (n=16). Both of the stretching techniques were applied to the hamstring once. Active knee extension angle, muscle activation during maximum voluntary isometric contraction (MVC), and static balance were measured prior to and following the application of each stretching technique. Both the static stretching and the PNF stretching groups displayed significant increases in knee extension angle compared to the control group. However, there weren’t any significant differences in muscle activation or balance between the groups.
Static stretching and PNF stretching techniques improved ROM without reduction in muscle activation, but neither of them exerted statistically significant effects on balance.