Effect of training in a sandy environment on foot morphology and function.

Background: Athletes need to enhance their foot function to improve their performance and prevent injuries and disability. Although foot function is believed to be improved by stabilizing the body on an unstable surface (e.g., a sandy beach), there have been no relevant studies to our knowledge. Here, we identified the differences in foot and balance functions between beach volleyball and volleyball players and investigated the effects of sandy surface training.

Methods: We included six male beach volleyball players (BVB group) and six male volleyball players (VB group). The following six parameters were measured and compared between the groups: foot morphology, plantar surface perception, isometric ankle muscle strength, toe grip strength, static balance, and dynamic balance.

Results: The BVB group had significantly higher values in sensation perception, isometric ankle dorsiflexion muscle strength, and toe grip strength in the standing posture, with significant intrinsic foot muscle dominance, compared to the VB group.

Conclusion: Playing barefoot increases the amount of tactile information received from the surface of the sole, which may lead to enhanced sensory perception by the foot. In addition, owing to the unstable sandy surface, the intrinsic muscles of the foot and lower leg may strengthen to maintain balance; therefore, training on a sandy surface may lead to improved foot and balance functions.