Table 2.
Heart rate variability measures in the cross-sectional study
| Sedentary | Moderate exercise | Endurance trained | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Young | Middle | Older | Young | Middle | Older | Young | Middle | Older | |
| No. of subjects (n) | 16 | 18 | 15 | 9 | 10 | 16 | 18 | 16 | 15 |
| RRi (ms) | 1014 ± 43 | 1023 ± 42 | 958 ± 40 | 929 ± 35 | 1075 ± 44 | 1010 ± 25 | 1143 ± 31§ | 1236 ± 27‡§ | 1216 ± 56‡§ |
| RRSD (ms) | 73 ± 10 | 40 ± 4* | 26 ± 3* | 56 ± 8 | 49 ± 5 | 35 ± 3 | 65 ± 7 | 60 ± 4‡ | 53 ± 7‡ |
| InHF (ln(ms2)) | 11.1 ± 0.3 | 9.6 ± 0.2* | 8.6 ± 0.3* | 10.5 ± 0.5 | 9.8 ± 0.4 | 9.3 ± 0.2 | 11.1 ± 0.3 | 10.7 ± 0.2 | 10.0 ± 0.4‡ |
*
P < 0.05 vs. young subjects within same activity group
‡
P < 0.05 vs. sedentary subjects of same age group
§
P < 0.05 vs. moderately exercising subjects of same age group; RRi, R-R interval; RRSD, R-R interval standard deviation; lnHF, high frequency R-R interval variability.