RESUMO
BACKGROUND: People with chronic low back pain (LBP) often demonstrate altered muscle activation with movements that involve the lumbopelvic region and hips. OBJECTIVE: The purpose of this study was to compare gluteus medius activity during sidelying hip abduction (SHA) and sidelying hip abduction-lateral rotation (SHALR) with and without instruction for lumbopelvic stabilization in people with and without chronic LBP. METHODS: A cross-sectional study was conducted recruiting participants with (n = 17) and without (n = 17) chronic LBP. Gluteus medius activity was recorded with surface electromyography during the performance of SHA and SHALR with and without instructions including the abdominal drawing-in maneuver for lumbopelvic stabilization. RESULTS: For SHA and SHALR, there was a significant main effect for instruction for stabilization indicated by a decrease in gluteus medius activity with instructions (p = .001, p < .001). There was not a significant main effect of chronic LBP on gluteus medius activity between groups for either activity. There was no significant interaction effect of pain and instruction for stabilization with SHA or SHALR. CONCLUSION: Knowledge of changes in gluteus medius muscle activation patterns with trunk stabilization instruction may help clinicians with assessment of exercise performance to optimize gluteus medius activation.