Joint torque parameters of lower limbs and the relationship with postural balance in young adults: a cross-sectional study

BACKGROUND: Different factors can influence the performance of postural control (PC), one of them being muscle function, which emerges as the neuromuscular capacity to generate tension adaptable to postural disturbances in the lower limbs. AIM: To investigate the influence of joint torque parameters of the lower limbs (hip, knee, and ankle) on the variables of postural balance, analyzed by static posturography in young adults. METHOD: This study included 25 young adults (23.08 ± 4.44 years) who were submitted to motor tasks alternating: the base of support; the surface and vision conditions on a force plate. Joint torque was measured using an isokinetic dynamometer. RESULTS: The hip-abduction, -adduction, and -extension torques were negatively associated with the variables of center of pressure displacement in several conditions, both the most challenging and the least challenging ones. The ankle torque (dorsiflexion and plantar flexion) was negatively associated with postural control only in the semi-tandem condition with a rigid surface and eyes open. On the other hand, the knee torque was positively associated with the center of pressure displacement. Power measurements were more associated with postural control than peak torque. CONCLUSION: In young adults, there seems to be a greater use of the hip strategy, with greater influence of hip torque in relation to ankle torque for postural balance control. Therefore, the strengthening of hip muscles could have an impact on postural control in young adults.