calculated from

Parameters	Normal weight		Overweight		Obese
Parameters	Supine	Tilt	Supine	Tilt	Supine	Tilt
RRi, ms	872 ± 88	653 ± 29^a	868 ± 97	710 ± 22^b	899 ± 66	758 ± 46^c
Spectral Parameters; RRi
Variance, ms²	1922 ± 436	1414 ± 332	1511 ± 433	877 ± 414	1521 ± 406	1574 ± 318
LF, ms²	629 ± 205	648 ± 147	301 ± 119^a	317 ± 75	219 ± 99^a	431 ± 192
LF, nu	63 ± 10	87 ± 10^a	47 ± 14^a	81 ± 15^b	33 ± 9^a	81 ± 8^c
HF, ms²	364 ± 46	94 ± 33^a	441 ± 170	74 ± 22^b	425 ± 141	84 ± 92^c
HF, nu	37 ± 10	13 ± 10^a	53 ± 14^a	19 ± 15^b	67 ± 9^ab	19 ± 8^c
LF/HF ratio	1.8 ± 0.33	7.3 ± 1.3^a	0.8 ± 0.51^a	4.1 ± 1.2^b	0.5 ± 0.31^ab	5.3 ± 1.2^c

Table 4: Spectral parameters calculated from R-R interval (RRi) time series obtained all trained volunteers in supine position and during the tilt test using autoregressive spectral analysis. All values were expressed as mean ± S.E.M. ^aP<0.05 vs. NW supine; ^bP<0.05 vs. NW supine; and ^cP<0.05 vs. OW supine. “nu” indicates normalized units.