Table 3.

Means and standard errors of HRV parameters of posture and work load levels.

	Supine			Upright
	1-back	2-back	p	1-back	2-back	p
SDNN	388.19 (70.20)	320.98 (46.07)	0.157	212.63 (35.68)	182.15 (45.58)	0.251
RMSSD	39.56 (3.81)	36.44 (3.60)	0.033*	34.66 (3.25)	31.84 (3.16)	0.061
TP	941.61 (126.62)	910.98 (122.38)	0.692	1190.58 (191.36)	1070.38 (164.10)	0.286
LFnu	0.58 (0.03)	0.58 (0.03)	0.820	0.67 (0.02)	0.69 (0.02)	0.254
HFnu	0.38 (0.03)	0.37 (0.03)	0.668	0.29 (0.02)	0.27 (0.02)	0.165
LF/HF	2.41 (0.50)	2.24 (0.40)	0.515	3.05 (0.37)	3.20 (0.38)	0.491

^*p < 0.05.