Table 3.

Basic statistical characteristics of postural stability parameters, evaluation of the significance of intergroup differences and effect size (2-ft test).

Variable [unit of measurement]	Two-feet test high-level group		Two-feet test low-level group		t	p	z	ES
	arithmetic mean	SD	arithmetic mean	SD
Area (mm2)	398.19	141.34	497.36	242.31	−0.79	0.45	−0.70	0.50
Convex hull area (mm2)	276.82	118.52	354.32	161.80	−0.86	0.41	−0.65	0.54
Length (mm)	217.09	43.12	247.85	59.77	−0.93	0.38	−0.71	0.59
Length AP (mm)	157.81	22.59	186.85	53.15	−1.12	0.29	−1.29	0.71
Length ML (mm)	115.84	37.53	125.87	26.78	−0.49	0.64	−0.27	0.30
Mean distance (mm)	7.74	1.32	7.61	2.70	0.10	0.92	0.10	0.06
Mean distance AP (mm)	6.73	1.81	6.51	2.66	0.15	0.89	0.12	0.09
Mean distance ML (mm)	2.93	0.83	2.87	0.74	0.11	0.91	0.07	0.07
RMS distance (mm)	8.75	1.30	8.76	3.21	−0.01	0.99	−0.01	0.00
RMS distance AP (mm)	7.94	1.69	8.00	3.23	−0.04	0.97	−0.04	0.02
RMS distance ML (mm)	3.45	0.91	3.45	0.91	−0.01	0,99	0.00	0.00
Mean velocity (mm/s)	10.85	2.16	12.39	2.99	−0.93	0.38	−0.71	0.59
Mean velocity AP (mm/s)	7.89	1.13	9.34	2.66	−1.12	0.29	−1.28	0.71
Mean velocity ML (mm/s)	5.79	1.88	6.29	1.34	−0.49	0.64	−0.27	0.30

*Statistically significant differences at p ≤ 0.05.

t, Student’s t-test value, U, Mann–Whitney U-test value (with continuity correction), z, standardized values, ES, effect size, > 0.2 = small, >0.5 = medium, >0.8 = large.