Contribution of hip abductor-adductor muscles on static and dynamic balance of community-dwelling older adults.

BACKGROUND: The previous studies have investigated causes of and risk factors for falls and impairment of functional capability in older adults. However, the biomechanical factors involved in functional performance and postural control, and the contribution of hip muscles, are still unknown. AIMS: The aim of the present study was to verify the association between the muscle function of hip abductors and adductors and static and dynamic balance, in a narrow base of support, in community-dwelling older adults. METHODS: Eighty-one older adults, including both women and men, were evaluated. Tandem gait and single-leg stance were used to assess static and dynamic balance, and an isokinetic dynamometer was used to analyze muscle function (peak torque and rate of torque development according to body weight). Data were analyzed by a multivariate linear regression test without adjustment and with adjustment using two models: adjustment I (sex) and adjustment II (age). RESULTS: There was a statistically significant association between peak torque of abductor in single-leg stance and tandem gait speed. The PT of hip adductors contributed to static balance performance, in a narrow base of support from the unadjusted data and from the adjusted data by sex. CONCLUSION: The findings of the present study are relevant, because if deficits in balance and functionality in older adults can be linked to a decline in maximum muscle strength of hip abductors, this parameter can be treated to maintain independence in older adults for as long as possible.