Effects of textured insoles on dynamic balance and ankle muscle activity in soccer players with and without chronic ankle instability

BACKGROUND: Chronic ankle instability (CAI) poses challenges in sports. Textured insoles (TI) are a promising intervention for enhancing dynamic balance in CAI athletes. This study aimed to investigate the effects of TI on dynamic balance performance and ankle muscle activity in soccer players with and without CAI. METHODS: Thirty-eight soccer players (19 CAI, 19 non-CAI) participated. Participants performed a modified star excursion balance test (mSEBT) while wearing TI and standard insoles (SI). The %SEBT reach distance and electromyography (EMG) activity of tibialis anterior (TA), medial gastrocnemius (MG), and peroneus longus (PL) were measured during maximum reached in each direction of the mSEBT. RESULTS: No significant effects or interactions were found between ankle conditions (CAI vs. non-CAI) or insole types (TI vs. SI) on %SEBT reach. However, CAI players showed greater MG activity in posteromedial and posterolateral direction (P=0.04, P=0.01). CONCLUSIONS: Overall, the application of TI did not have immediate effects on dynamic balance performance or ankle muscle activity in either CAI or non-CAI soccer players. Nonetheless, CAI players seemed to employ a different ankle strategy involving the MG muscle, possibly to control stability during dynamic movement, particularly in the posteromedial and posterolateral directions.