An electromyography system, kinetics and kinematics variables are insufficient to predict the failure-to-recover an impending loss of balance

Abstract

The body balance maintenance is performed through synchronized motor strategies, to preserve functional mobility. The purpose of this study is to compare the balance recovery mechanisms among young adults in an impending loss of balance. Thirty healthy young adult [age 24.87±4.16; weight 72.69±14.73 kg; growth 1.72±0.08 m] participated in the study. Seven perturbations were applied with a progressive velocity of the perturbation, in the antero-posterior direction. The following variables were analyzed: active time of muscle contraction, latency and displacement amplitude of the center of pressure, and angular variation of the ankle. For each perturbation, the subjects were classified according to their ability to recover balance: “no step” and step forward or hold the rope of the safety vest support. There were no significant differences between groups in all variables analyzed. At lower velocities of displacement, the group of “no step” presented greater angular variation for the knee joint, lower pressure center displacement range, and lower active time of normalized contraction of the muscle anterior tibial. The results suggest that the variables analyzed were insufficient to identify significant differences in the adoption of strategies for recovery of balance in an impending loss of balance.