Effects of Visual Biofeedback on Symmetrical Movements During Bridge Exercise With Sling.

CONTEXT Asymmetrical movements of trunk and lower-extremity are common during the bridge exercise on the unstable condition. However, no studies have investigated whether visual biofeedback of pressing pressure on the unstable surface changes muscle activation patterns of trunk and hip extensors and pelvic rotation during the bridge exercise. OBJECTIVE To investigate how visual biofeedback of pressing pressure influences symmetrical activity of lumbar and hip extensor and pelvic rotation. DESIGN Cross-sectional study. SETTING Laboratory. PARTICIPANTS Twenty healthy males participated in this study. INTERVENTIONS The participants performed 2 versions of the bridge exercise: the standard bridge exercise and the bridge exercise with visual biofeedback using amount of pressing pressure on the sling. MAIN OUTCOME MEASURES Surface electromyography was used to measure the symmetry (ie, the difference between dominant and nondominant sides) of muscle activation in the bilateral erector spinae, gluteus maximus, and hamstring muscles, and motion sensors were used to assess pelvic rotation. Symmetry of pressing pressure was measured using a tension meter. RESULTS The differences between the dominant and nondominant pressing pressures and differences between the electromyography activity of the dominant and nondominant erector spinae, gluteus maximus, and hamstring were significantly smaller during the bridge exercise with visual biofeedback than during the standard bridge exercise (P < .05). In addition, there was significantly less pelvic rotation during the bridge exercise with visual biofeedback than during the standard bridge exercise (P < .05). CONCLUSIONS The present findings suggest that visual biofeedback strategy may be a useful method for enhancing the symmetrical activation of the erector spinae, gluteus maximus, and hamstring and for reducing pelvic rotation during the bridge exercise on the unstable surface.