Effects of a 4-week exercise program on balance using elastic tubing as a perturbation force for individuals with a history of ankle sprains.

STUDY DESIGN Randomized controlled trial with pretraining, posttraining, and follow-up repeated measures. OBJECTIVE To determine the effectiveness of a 4-week elastic resistance exercise program on balance in subjects with and without a history of sprained ankles. BACKGROUND Several researchers have suggested that improving balance may help alleviate the symptoms of functional ankle instability and reduce the rate of recurrent ankle sprains. METHODS AND MEASURES Forty subjects (20 males, 20 females; 20 subjects with chronic ankle instability [CAI], 20 healthy) participated in the study. Ten subjects (5 males, 5 females) from each CAI and healthy group were randomly assigned to either the exercise or control group, resulting in a total of 4 groups. Total travel distance of the center of pressure, monitored using a force platform, was measured before training, after 4 weeks of training, and at a 4-week follow-up. RESULTS There were no interactions between gender, ankle sprain history, or training groups. Balance significantly improved in subjects with and without a history of ankle sprains following 4 weeks of elastic resistance exercises. Mean improvement in balance for the exercise group following training, reflected through a decrease in total travel distance, was -11.1 cm (95% confidence interval: -14.0 to -8.2 cm). These improvements in balance were retained 4 weeks after training. CONCLUSIONS Balance was improved after 4 weeks of elastic resistance exercise in subjects with and without a history of lateral ankle sprains. Balance improvements persisted 4 weeks following the treatment cessation.