Sex differences in magnitude and direction of interlimb asymmetries in eccentric hip abduction strength

ABSTRACT Objectives This study had three aims 1) To investigate the effect of sex and leg dominance on eccentric hip abduction (HABd) strength 2) determine sex differences in magnitude of asymmetry and 3) determine the association of sex and direction of asymmetry. Design Cross-sectional study Setting University laboratory Participants 61 athletes (39 males, 22 females) participating in sports requiring change of direction (COD) Main outcome measures Eccentric HABd strength was tested in both legs for all participants using an eccentric break test with a Handheld dynamometer (HHD). Results This study found no interaction of sex and leg dominance on eccentric HABd strength (absolute: p=0.52, adjusted p=0.10). Significant main effects were found for leg dominance (absolute: p=<0.01, η2=0.22, adjusted: p=0.00, η2=0.16) and sex on absolute (p=<0.01, η2=0.31) but not adjusted eccentric HABd strength (p=0.08, η2=0.05). Females demonstrated statistically significant higher magnitude of asymmetry values (15.3%) compared to males (9.8%) (p=0.01). There was no association between sex and direction of asymmetry (absolute: χ2(1) = .24, p = .62, adjusted: χ2(1) = 1.15, p = .28). Conclusion Female athletes are likely to have greater eccentric HABd asymmetry which may predispose them to adverse lower extremity biomechanics and increase injury risk.