Comparison of cardiovascular load and nocturnal HRV on work and non-workdays (n=19)
| Workdays | Non-workdays | β (SE) | P value | Effect size (f2)* | |
| Heart rate (beats/min) | |||||
| 24-hour | 83.8 (1.2) | 78.5 (1.4) | 5.4 (1.3) | <0.001 | 0.16 |
| Waking | 89.4 (1.3) | 83.0 (1.5) | 6.4 (1.3) | <0.001 | 0.21 |
| Nocturnal | 69.2 (1.0) | 66.3 (1.4) | 2.9 (1.5) | 0.056 | 0.05 |
| Non-work time | 84.8 (1.2) | 82.9 (1.5) | 1.9 (1.3) | 0.162 | 0.02 |
| Systolic BP (mm Hg) | |||||
| 24-hour | 126.0 (1.7) | 124.0 (1.8) | 2.0 (2.0) | 0.317 | 0.06 |
| Waking | 131.7 (1.6) | 129.0 (1.8) | 2.7 (1.9) | 0.157 | 0.10 |
| Nocturnal | 113.7 (2.5) | 113.5 (3.0) | 0.2 (3.5) | 0.952 | 0.00 |
| Non-work time | 132.5 (1.9) | 128.6 (2.1) | 3.8 (2.5) | 0.120 | 0.15 |
| Diastolic BP (mm Hg) | |||||
| 24-hour | 75.2 (1.0) | 72.6 (1.1) | 2.7 (1.1) | 0.019 | 0.30 |
| Waking | 80.9 (1.2) | 77.0 (1.3) | 3.9 (1.4) | 0.006 | 0.41 |
| Nocturnal | 63.2 (1.4) | 63.1 (1.6) | 0.1 (1.7) | 0.940 | 0.00 |
| Non-work time | 80.0 (1.2) | 76.7 (1.3) | 3.3 (1.5) | 0.023 | 0.31 |
| Nocturnal HRV | |||||
| Average RR (ms) | 909.75 (19.27) | 936.29 (21.73) | −26.54 (14.87) | 0.074 | 0.05 |
| RMSSD (log) | 3.40 (0.15) | 3.26 (0.14) | −0.13 (0.07) | 0.077 | 0.04 |
| SDNN (ms) | 39.85 (3.48) | 42.14 (3.71) | −2.29 (1.90) | 0.230 | 0.03 |
| LF (log) | 6.18 (0.20) | 6.45 (0.21) | −0.27 (0.12) | 0.025 | 0.01 |
| HF (log) | 5.22 (0.30) | 5.56 (0.31) | −0.33 (0.14) | 0.014 | 0.05 |
| LF/HF ratio | 4.75 (0.73) | 4.41 (0.76) | 0.35 (0.33) | 0.301 | 0.06 |
Outcome data are presented as least squared means (SE).
All models were adjusted for age, BMI, smoking status, fitness, and the resting value of the outcome of interest (except for HRV).
*The magnitude of effect (f2) is calculated for the effect of day type (work vs non-workday) and can be interpreted as small: f2 ≥0.02, medium: f2 ≥0.15, and large: f2 ≥0.35.
BMI, body mass index; BP, blood pressure; HF, high-frequency power; HRV, heart rate variability; LF, low-frequency power; LF/HF Ratio, low-frequency to high-frequency ratio; RMSSD, root mean square successive difference; SDNN, SD of the normal to normal; β (SE), beta coefficient (SE).