Combining three-dimensional ankle exercises with short-foot training improves proprioception and dynamic balance in female karatekas with flatfoot: A randomized controlled trial.

OBJECTIVE

This study aimed to assess the effectiveness of a comprehensive training protocol including three-dimensional ankle exercise combined with short-foot exercise (SF-3DAE), compared to short-foot exercise (SFE) alone, in improving navicular drop, ankle proprioception, and dynamic balance in female karate athletes with flatfoot.

DESIGN

Randomized controlled trial.

SETTING

Rehabilitation laboratory.

PARTICIPANTS

Thirty-four female karate athletes with flatfoot (mean age 20.79 ± 2.72 years) were randomized to SF-3DAE (n = 17) or SFE (n = 17).

MAIN OUTCOME MEASURES: Navicular drop (Brody method), ankle proprioception (angle reproduction error), and dynamic balance (Y-Balance test).

RESULTS

Group × time interactions were significant for all outcomes, with greater improvement in the SF-3DAE group for navicular drop (P = 0.001), proprioception (P < 0.001), and dynamic balance (P < 0.001). In the SF-3DAE group, navicular drop decreased by 2.24 mm, proprioception error by 3°, and total Y-Balance reach increased by 17.49 percentage points of leg length; corresponding changes in the SFE group were 1.16 mm, 1.59°, and 7.82 percentage points (P < 0.001). An individual-level responder analysis showed that most participants in both groups achieved reliable improvement in navicular drop, proprioception, and anterior/total balance, whereas the added benefit of SF-3DAE was concentrated in posteromedial and posterolateral balance, where responder rates were markedly higher than in the SFE group.

CONCLUSION

Adding 3DAE to SFE produced greater improvements in foot posture, proprioception, and dynamic balance than SFE alone, with the clearest advantage in multidirectional balance, a pattern consistent with the greater peroneus longus and evertor recruitment associated with the diagonal movement patterns of 3DAE. Because the SF-3DAE group also received a greater volume of supervised exercise, this contribution cannot be fully separated from a general training-volume effect. Whether these improvements translate into enhanced athletic performance or reduced injury risk was not assessed and requires further study.

TRIAL REGISTRATION: XXX (registered 12/28/2022).