Hip Adduction:Abduction Ratios and Force Outputs Across Common Testing Positions in Healthy Elite-Level Female Soccer Players

Context : ForceFrame values for hip adduction, abduction, and adduction:abduction strength ratio do not currently exist in the literature for female soccer players. Such values are needed and would inform both strengthening programs and rehabilitative exercise prescription. The purpose of this study was to compare hip adduction and abduction force outputs and hip adduction:abduction ratios across common testing positions in healthy elite-level female soccer players. Design : Cross-sectional cohort study. Methods : Isometric hip adduction and abduction force outputs and ratios were obtained from 32 female soccer players, using a ForceFrame, in the 0° hip-flexion long-lever position, 0° hip-flexion short-lever position, and 45° hip-flexion position. A 1-way repeated-measures analysis of variance was used to examine differences in force output between testing positions. Statistical significance was accepted as P ≤ .05. Results : Analysis of variance revealed no significant differences in hip adduction force output between the 45° hip-flexion position (266.4 [55.77] N) and the 0° hip-flexion short-lever position (250.1 [70.56] N), P = .32. Hip abduction force outputs were significantly greater (29%) in the 45° hip-flexion position (260.9 [44.43] N) compared with the 0° hip-flexion short-lever position (185.2 [54.84] N), P < .001. Hip adduction:abduction ratio was significantly greater in the 0° hip-flexion short-lever position (1.41 [0.35]) compared with the 45° hip-flexion position (1.03 [0.17]), P < .001, and the 0° hip-flexion long-lever position (0.87 [0.21]), P = .001. The 45° hip-flexion position also demonstrated significantly greater ratios than the 0° hip-flexion long-lever position, P = .052. Conclusions : These hip adduction:abduction strength ratios should inform practitioners when prescribing strength or rehabilitative exercise to female soccer players. These findings also demonstrate that different testing positions most likely favor different gluteal muscle groups and their respective length tension relationships when the hip position is altered.