Influence of Textured Insoles on Dynamic Postural Balance of Young Dancers

BACKGROUND: Postural balance (PB) is a significant factor in dance performance and injury prevention. We aimed to determine whether the use of textured insoles inserted into casual walking shoes of dancers improved their dynamic PB and whether dancers with previous injury manifested different dynamic PB compared with non-injured dancers. METHODS: In this crossover design study, 26 ballet dancers from the Australian Ballet School, aged 14-19 yrs, were divided into two groups matched by sex and class levels. Group 1 wore the textured insoles in their walking shoes for at least 2 hrs/day during weeks 1 to 4 of the study, and group 2 wore the textured insoles in their walking shoes during weeks 5 to 8. Reports from the school medical staff identified dancers who had previous injuries. All participants were tested pre-intervention and at 4 and 8 weeks by an accelerometer for dynamic PB (average acceleration magnitude, root mean square acceleration, range, and mean frequency) during single-leg fondu, flexing and extending of the knee. FINDINGS: Interactions (group x time) were found in dynamic PB measured in the mediolateral direction, indicating significant differences between the groups at the three testing times. Furthermore, both previously injured and noninjured dancers manifested significant time effects from pre-intervention to 8 weeks, indicating a significant improvement in their PB after using the textured insoles. CONCLUSION: Textured insoles can improve the dynamic PB of ballet dancers and can also be useful as a routine intervention. PB was improved among both dancers with previous injury and non-injured dancers.