Table 2.

Variance of center of mass (COM) position during quiet standing with perturbation (dynamic condition).

(unit: mm2)	Before	After	Trend	t	p	ES
Forward perturbation
Reaction phase	223.74 ± 93.40	192.51 ± 72.35	—	1.25	0.23	0.37
Recovery phase	126.18 ± 66.24	89.51 ± 45.83	↓	2.56	0.02	0.64
Backward perturbation
Reaction phase	251.34 ± 180.59	175.30 ± 130.06	—	1.21	0.245	0.48
Recovery phase	212.20 ± 144.88	104.28 ± 63.81	↓	3.08	0.007*	0.96
Lateral perturbation
Reaction phase	217.75 ± 76.78	182.88 ± 21.21	—	1.99	0.63	0.62
Recovery phase	121.18 ± 58.78	81.33 ± 32.96	↓	3.63	0.002*	0.84

*p < 0.008, ES: effect size.