Immediate Effects of Leg-Press Coordination Training on Ankle Sway in Individuals With Chronic Ankle Instability: A Randomized Controlled Trial

Objectives This study aimed to determine the effects of leg-press coordination training on immediate ankle sway in individuals with chronic ankle instability (CAI). Methods Participants with CAI (age 19.8 ± 1.0 years, seven men and 17 women) were randomly allocated to a control group (CON), which performed regular leg-press training, or a coordination training group (CT), which performed coordination training using a leg-press device. The main outcome measure was the average angular jerk cost of the ankle joint in the Y-balance test (YBT), and the secondary outcome measures were the maximum ankle and hip joint angles, maximum reach distance in the YBT, ankle proprioception, and weight-bearing dorsiflexion angle. Results A significant group × period (pre- and post-intervention) interaction in the ankle average angular jerk cost was observed in the YBT in anterior reaching and posteromedial reaching ankle plantar flexion/dorsiflexion (anterior reaching: p = 0.03, posteromedial reaching: p < 0.01) as well as in adduction/abduction (posteromedial reaching: p = 0.02). The average ankle angular jerk cost in the CT group was significantly lower at post-intervention than at pre-intervention. Conclusions Leg-press coordination training immediately reduces ankle sway in individuals with CAI.