Table 3.
Differences of mean HRV indices compared with the control group.
| Primary outcomes | Intervention | Control | Post-test–pre-test | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Pre-test | Post-test | Pre-test | Post-test | Intervention-control | |||||
| Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD | 95% CI | T-value | P-value | Cohen's d | |
| SDNN (ms) | 33.9 ± 9.2 | 39.6 ± 12.1 | 36.5 ± 9.2 | 33.9 ± 10.8 | 9.4 ± 3.5 | 2.3,16.6 | 2.718 | 0.012 | 1.09 |
| RMSSD (ms) | 32.1 ± 10.9 | 40.5 ± 16.0 | 31.3 ± 12.0 | 30.1 ± 15.1 | 10.5 ± 5.8 | −1.6,22.5 | 1.8 | 0.085 | 0.73 |
| PNN50 (%) | 12.1 ± 10.6 | 20.9 ± 15.3 | 13.8 ± 12.5 | 13.8 ± 16.1 | 9.9 ± 6.3 | −3.2,22.9 | 1.566 | 0.131 | 0.63 |
| LF (log) | 6.2 ± 0.6 | 6.1 ± 0.7 | 6.3 ± 0.6 | 6.2 ± 0.8 | 0.01 ± 0.3 | −0.6,0.6 | −0.027 | 0.979 | 0.00 |
| HF (log) | 5.7 ± 0.6 | 6.2 ± 0.7 | 5.9 ± 0.8 | 5.5 ± 1.2 | 0.9 ± 0.4 | −1.7, −0.2 | −2.545 | 0.018 | 1.08 |
| LF/HF | 2.2 ± 1.8 | 1.3 ± 1.1 | 2.0 ± 1.5 | 3.2 ± 2.8 | −2.2 ± 1.0 | −4.3, −0.03 | −2.096 | 0.047 | 0.84 |
BMI, body mass index; SAS, Zung's Self-rating Anxiety Scale; SDNN, standard deviation of all R-R intervals; RMSSD, square root of the sum of the mean of the difference between adjacent RR intervals; LF, low frequency power; HF, high frequency power.