Title

The Acute Effect of Hip External Rotator Stretches on Hip Internal Rotation Range of Motion

Document Type

Article

Abstract

The effects of static stretching on range of motion have been widely studied. However, most of the research has focused on hamstring stretching. The purpose of this study was to compare the acute effect of two commonly used static stretches on hip internal rotation passive range of motion (HIR-PROM). Participants (N=30, 15 male, 15 female; 22±1.8 yrs.; 173.5±8.5cm; 73.8±12.7 kg) were randomly assigned (with gender controlled) to one of three groups: control, figure 4 stretch and modified lunge stretch. Pre-test and post-test HIR-PROM was measured on each subject’s non-dominant hip. HIR-PROM was measured with a goniometer from the prone position. The knee was flexed to 90° and the hip was passively internally rotated. Each subject completed a 10 minute warm-up on a cycle ergometer. Upon completion of the warm-up the two stretching groups completed the respective stretching protocol while the control group rested on a table. A mixed method factorial ANOVA was used to analyze main effects (group, time) and if a significant interaction occurred. There was no interaction or group main effect (p>0.05). However, there was a time main effect regardless of group assignment (F1,27=33.151, p<0.001). There appears to be no enhanced acute effect on HIR-PROM when a figure 4 or modified lunge stretch is implemented in addition to a 10 minute warm-up on a stationary bike. In an effort to improve efficiency clinicians may choose to forgo post-cycle ergometer warm-up figure 4 or modified lunge stretching when attempting to acutely increase HIR-PROM.