Table 2.

Marker sway parameters (mean ± SD) for firm and compliant surface balance trials with different mechanical noise bandwidths introduced.

Balance surface	Units	Parameter	Vibration bandwidth			P-values
			Control (C)	Wide (W)	Narrow (N)	C versus W	C versus N	N versus W
Firm	mm	ML range	$8.6\pm 2.0$	$8.9\pm 2.2$	$9.0\pm 3.5$	0.677	0.709	0.919
		AP range	$18.0\pm 3.0$	$16.7\pm 3.3$	$17.4\pm 3.6$	0.221	0.566	0.478
	mm/s	ML speed	$1.6\pm 0.4$	$1.7\pm 0.4$	$1.7\pm 0.6$	0.316	0.348	0.548
		AP speed	$2.9\pm 0.6$	$2.8\pm 0.6$	$2.8\pm 0.5$	0.416	0.399	0.963
	mm${}^2$	Swept area	$148.8\pm 52.2$	$144.5\pm 50.3$	$140.9\pm 63.3$	0.838	0.734	0.828
Compliant (foam)	mm	ML range	$21.3\pm 6.3$	$19.1\pm 5.3$	$20.7\pm 5.8$	0.017	0.496	0.034
		AP range	$29.6\pm 7.0$	$28.5\pm 7.8$	$29.4\pm 5.9$	0.508	0.855	0.369
	mm/s	ML speed	$4.0\pm 1.0$	$3.7\pm 0.8$	$3.9\pm 1.0$	0.043	0.148	0.220
		AP speed	$5.2\pm 0.9$	$4.8\pm 1.0$	$5.0\pm 1.1$	0.049	0.297	0.037
	mm${}^2$	Swept area	$598.6\pm 263.5$	$523.2\pm 261.1$	$607.8\pm 251.8$	0.156	0.828	0.009