Re-examination of hip flexion angle-torque characteristics.

BACKGROUND: Hip flexion angle-torque may not be measured accurately due to the measurement posture. OBJECTIVE: Maximum isometric hip flexion torque was measured while excluding the effects of postural retention function and compensatory motion. METHODS: Experiment 1: Maximum isometric flexion torque of the hip joint was measured at 0^∘, 30^∘, 60^∘, 90^∘, and 105^∘ in 195 participants. Experiment 2: Maximum isometric hip flexion torque of 33 participants was measured in standing and supine position at 0^∘ hip flexion and in end-sitting and supine position at 105^∘. RESULTS: Experiment 1: No interaction was observed between sex and hip angle, and hip flexion torque was minimum at 0^∘ hip flexion and maximum at 105^∘ hip flexion in both sexes (p < 0.01). Experiment 2: An interaction between measurement position and hip angle was observed, with maximum isometric flexion torque being greater in the supine position than in the standing position (p < 0.01). Maximum isometric hip flexion torque was greater at 105^∘ than at 0^∘ flexion (p < 0.01). CONCLUSIONS: Maximum isometric hip flexion torque showed greater joint angle-torque characteristics in deep flexion than in shallow flexion of the hip when excluding the effects of postural retention function and compensatory motion. [ABSTRACT FROM AUTHOR]