Table 2. Postural stability data for the 3 groups. All values are mean ± standard deviation. Neutral Flatfoot High-arch P values Effect sizesb Neutral vs Flatfoot Neutral vs High-arch Flatfoot vs High-arch Time during APA (s) a 1.13 ± 1.40 0.96 ± 1.21 0.66 ± 0.37 0.744 0.08 0.00 0.23 COP displacement during APA (m) 0.21 ± 0.03 0.18 ± 0.07 0.16 ± 0.04 0.110 0.57 1.50 0.38 COP excursion during APA (m)a 0.10 ± 0.01 0.08 ± 0.03 0.08 ± 0.02 0.060 0.27 0.54 0.26 Time to new stability point (s)a 4.95 ± 2.04 3.87 ± 2.30 4.70 ± 1.42 0.627 0.23 0.07 0.16 AP COP displacement during the first 3 s after TNSP (m) 0.15 ± 0.03 0.21 ± 0.05* 0.15 ± 0.05 0.020 1.37 0.16 1.28 ML COP displacement during the first 3 s after TNSP (m) 0.17 ± 0.04 0.23 ± 0.06* 0.17 ± 0.04 0.023 1.24 0.03 1.25 Resultant COP displacement during the first 3 s after TNSP (m) 0.25 ± 0.05 0.34 ± 0.08* 0.25 ± 0.07 0.012 1.40 0.11 1.37 APA: anticipatory postural adjustments; COP: center of pressure; TNSP: time to new stability point; AP: anteroposterior; ML: mediolateral. a The data were not normally distributed. b Cohen’s d and r were calculated when the data were normally distributed and not normally distributed, respectively. * Significant differences compared with neutral and high-arch groups on post-hoc Tukey honestly significant difference tests (p < 0.05).