Purpose: This research was conducted to determine whether professional athletes with chronic ankle instability (CAI) exhibit differences in maintaining balance under conditions with and without visual information. Methods: Forty-five elite players with CAI were classified into soccer, volleyball, and basketball groups(n=15). All participants perform static single-leg balance test in conditions wherein visual information was provided and withheld. The center of pressure (CoP) oscillation parameters was measured. The data were examined through an ANOVA and Tukey’s test. Results: A significant difference was found between the soccer and volleyball players(P=0.034) in terms of anteroposterior CoP displacement. Furthermore, there was a significant difference between soccer compared with volleyball(P=0.001) and basketball (P=0.02) group regarding mediolateral sway and sway area (P=0.003 and P=0.03 respectively) that they performed test with their eyes open. A significant difference occurred between the soccer and volleyball players with respect to anteroposterior and mediolateral sway (P=0.002 and P=0.04, respectively) as well as sway area (P=0.004) that they performed test with their eyes closed. Conclusion: Given the necessity of maintaining good balance in sports, volleyball coaches should design programs that reduce the reliance of players on visual information and strengthen their proprioceptive abilities through increased challenge to their proprioceptive senses.
