Table 3.
The effect of HIIT on cardiovascular autonomic measures.
| Control (n = 11) |
Intervention (n = 11) |
Between-group p value | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Baseline | Post-treatment | p-value | Δ (%) | Baseline | Post-treatment | p-value | Δ (%) | ||
| Heart rate variability | |||||||||
| RRI (ms) | 920 ± 6 | 930 ± 32 | 0.505 | 1.1 | 954 ± 49 | 973 ± 53 | 0.386 | 2 | 0.672 |
| SDNN (ms) | 42 ± 3 | 56 ± 14 | 0.424 | 33 | 53 ± 14 | 53 ± 15 | 0.962 | 0 | 0.340 |
| RRI LFnu (%) | 53 ± 6 | 51 ± 5 | 0.509 | 3.8 | 47 ± 6 | 48 ± 5 | 0.477 | 2.1 | 0.992 |
| RRI HFnu (%) | 47 ± 6 | 49 ± 5 | 0.549 | 4.3 | 53 ± 6 | 52 ± 5 | 0.477 | 1.9 | 0.984 |
| RRI LF/HF | 1.20 ± 0.29 | 1.0 ± 0.17 | 0.11 | 16.7 | 0.9 ± 0.21 | 0.73 ± 0.07 | 0.308 | 18.9 | 0.203 |
| Blood pressure variability | |||||||||
| SBP LFnu (%) | 37 ± 3 | 36 ± 2 | 0.755 | 2.7 | 34 ± 3 | 33 ± 2 | 0.681 | 2.9 | 0.608 |
| SBP HFnu (%) | 28 ± 5 | 28 ± 3 | 0.954 | 0 | 19 ± 4 | 15 ± 3 | 0.021* | 21 | 0.003** |
| SBP LF/HF | 1.06 ± 0.26 | 0.91 ± 0.14 | 0.281 | 14.2 | 0.86 ± 0.21 | 0.73 ± 0.1 | 0.328 | 15.1 | 0.169 |
| DBP LFnu (%) | 41 ± 3 | 39 ± 2 | 0.456 | 4.9 | 35 ± 4 | 34 ± 3 | 0.53 | 2.9 | 0.24 |
| DBP HFnu (%) | 21 ± 5 | 21 ± 4 | 0.892 | 0 | 21 ± 6 | 20 ± 6 | 0.894 | 4.8 | 0.884 |
| DBP LF/HF | 1.19 ± 0.29 | 1.01 ± 0.17 | 0.139 | 15.1 | 0.91 ± 0.21 | 0.73 ± 0.07 | 0.286 | 19.8 | 0.200 |
| Baroreflex receptor sensitivity | |||||||||
| Total slope mean (ms/mmHg) | 10.8 ± 1.4 | 10.3 ± 1.0 | 0.716 | 4.6 | 18.0 ± 5.5 | 19.1 ± 4.75 | 0.093 | 6.1 | 0.150 |
Δ: % change from baseline; RRI: R-R interval; SDNN: standard deviation of R-R interval; LFnu: low-frequency normalised units; HFnu: high-frequency normalised units; LF/HF: low frequency:high frequency ratio; SBP: systolic blood pressure; DBP: diastolic blood pressure.
*
p<0.05 significance,** p < 0.01 significance.