. 2005 Jul 19;10(3):324–329. doi: 10.1111/j.1542-474X.2005.00636.x

Table 2.

The Change in the Time and Frequency Domain Parameters of Heart Rate Variability During Three Phases of the Study in Both Groups

Variable	S	CR	HGE
Smokers
RR	815 ± 102	820 ± 117^a	759 ± 72^b
SDNN	64 ± 10	67 ± 17^a	44 ± 15^b
RMSSD	35 ± 12	40 ± 23^a	29 ± 9^b
LF	184 ± 59	145 ± 58^b	230 ± 64^b
HF	172 ± 84	205 ± 95^b	105 ± 55^b
LF/HF ratio	1.3 ± 0.6	0.9 ± 0.6^b	2.6 ± 1.1^b
Nonsmokers
RR	808 ± 96	861 ± 72^b	721 ± 91^b
SDNN	78 ± 22	85 ± 26^b	67 ± 11^b
RMSSD	54 ± 30	68 ± 34^b	41 ± 18^b
LF	162 ± 52	111 ± 63^b	210 ± 78^b
HF	205 ± 76	297 ± 104^b	150 ± 72^b
LF/HF ratio	0.9 ± 0.5	0.4 ± 0.3^b	1.7 ± 0.9^b

^aP > 0.05 versus supine; ^bP < 0.05 versus supine.

Abbreviations as in text.