Correlation between Two Gluteus Maximus Strength Assessment Method in Subjects with and without Low Back Pain

Background The gluteus maximus (GMax) plays a vital role in maintaining trunk stability, controlling hip extension, and supporting pelvic alignment. GMax weakness is commonly observed in individuals with low back pain (LBP), and strengthening this muscle is a key component of rehabilitation programs for LBP. Although Prone Hip Extension (PHE) is a conventional method for assessing hip extensor strength, it may induce compensatory activation of synergistic muscles, potentially exacerbating LBP. More recently, the Gluteus Squeeze (GS) method has gained popularity in clinical practice as a safer and more convenient alternative. However, research validating the GS method remains limited. Objectives To investigate the correlation between GS and PHE strength measurements in individuals with and without LBP. Methods A total of 52 participants (26 with LBP and 26 without LBP) were recruited. GS strength was measured using a belt-connected tensiometer, while PHE strength was assessed in the prone position using a hand-held dynamometer. All participants received standardized instructions for both tasks, and measurements were taken bilaterally. Independent t-tests and Pearson correlation analyses were conducted. Results A strong positive correlation was observed between GS and PHE strength in both groups. In participants without LBP, significant bilateral correlations were found and, similarly, strong bilateral correlations were also observed in those with LBP. Conclusions This study demonstrated a strong positive correlation between GS and PHE strength assessments in individuals with and without LBP. These findings suggested that the GS method may serve as a safer to PHE for evaluating GMax strength in clinical settings, particularly in patients with LBP.