Postural stability during one-leg stance on an unstable moving platform and its relationship with each leg.

This study examined the laterality of the supporting leg in postural stability during a one-leg stance test on an unstable moving platform and its practice effect. 30 male university students were evaluated using the omnidirection stability index (OSI) during a one-leg stance test on an unstable moving platform (three trials). The leg used when kicking a ball was defined as the manipulation leg (ML) and the supporting leg was defined as the non-manipulation leg (NML). According to the two-way repeated measures analysis of variance (ANOVA; trials x legs), a statistically significant difference was observed only on the leg factor, and OSI values of the second and third trials were less for the ML than the NML. The correlation between both legs was statistically significant but not high. The ML was superior to NML with regard to stability, and no practice effect with trials was evident in either leg.