Tehran University of Medical Sciences Journal of Modern Rehabilitation 2538-385X 0 - 2026 09 12 1483 1483 Masoud Azizian Department of Sport Rehabilitation, Faculty of Sport Sciences, Bu-Ali Sina University, Hamedan, Iran Ali Yalfani Department of Sport Rehabilitation, Faculty of Sport Sciences, Bu-Ali Sina University, Hamedan, Iran 2025 12 19 2026 05 24 Background: Chronic ankle instability (CAI) induces a disorder of the central nervous system, in which brain waves play an important role in regulating these factors. The aim of this study was to investigate the immediate effect of dual-task training (neuromuscular and cognitive) on brain electrical activity, pain severity, and foot and ankle disability index (FADI) in athletes with CAI. Methods: This study a single-blind randomized control trial (RCT). Participants were 44 young male and women athletes (N=27 male: N=17 women) with CAI who were randomly divided into two groups; dual-task training group and control group. The immediate effect of dual-task training was performed for 30 minutes. Outcome measures were brain electrical activity (electroencephalography Medina Teb Company, Iran was employed), pain severity (10-centimeter visual analog scale) and disability. Results: The results indicated that dual-task training significantly improved brain electrical activity and reduced pain severity. Significant reductions in pain were observed (P < 0.001, η² = 0.493), along with decreased theta wave activity at O1 and O2 (P < 0.001, η² = 0.837; P < 0.001, η² = 0.898). In contrast, alpha and beta wave activities significantly increased at both O1 and O2 electrodes (beta: P ≤ 0.001, η²ₚ = 0.702 and 0.898). Conclusion: The findings of this study indicate that dual-task training has an immediate effect on enhancing brain electrical activity in the O1 and O2 regions and reducing pain severity. Based on these acute findings, physiotherapists and sports rehabilitation practitioners may consider incorporating dual-task training as a complementary approach aimed at improving central nervous system function. https://jmr.tums.ac.ir/index.php/jmr/article/view/1483