Balance Training Enhances Motor Coordination During a Perturbed Sidestep Cutting Task

Study Design Controlled laboratory study. Background Balance training may improve motor coordination. However, little is known about the changes in motor coordination during unexpected perturbations to postural control following balance training. Objectives To study the effects of balance training on motor coordination and knee mechanics during perturbed sidestep cutting maneuvers in healthy adults. Methods Twenty‐six healthy men were randomly assigned to a training group or a control group. Before balance training, subjects performed unperturbed, 90degree sidestep cutting maneuvers and 1 unexpected perturbed cut (10‐cm translation of a movable platform). Participants in the training group participated in a 6‐week balance training program, while those in the control group followed their regular activity schedule. Both groups were retested after a 6‐week period. Surface electromyography was recorded from 16 muscles of the supporting limb and trunk, as well as kinematics and ground reaction forces. Motor modules were extracted from electromyography by nonnegative matrix factorization. External knee abduction moments were calculated using inverse dynamics equations. Results Balance training reduced the external knee abduction moment (33% +/‐ 25%, P