Table 3.
Mean and the associated SD, differences between the CVs of the James One (CVJ) and the Polar H10 (CVP), Hg value, mean differences (bias) and the associated SD, for all the pairs of HRV metrics obtained at rest. Using Cohen’s guidelines, an Hg value equal to 0.2 represents a small effect, 0.5 a medium effect, and 0.8 a large effect [38,39]. The agreement between the parameters is shown as LCCC. Values higher than 0.99 represent an almost perfect agreement, substantial and moderate agreement when lower than 0.99 and higher than 0.95, and a poor agreement if lower than 0.95 [41,42]. BA ratios lower than 0.1 represent a good agreement, higher than 0.1 and lower than 0.2 represent a moderate agreement, and higher than 0.2 a poor agreement [13,34,47].
| Mean ± SD James One |
Mean ± SD Polar H10 |
CVJ – CVP (%) |
Hg | LCCC | Bias ± SD | LoA Upper; Lower |
BA Ratio | |
|---|---|---|---|---|---|---|---|---|
| Mean int. (ms) | 778 ± 80.8 | 782 ± 81.1 | 0.015 | −0.046 | 0.998 | −3.80 ± 0.45 | −2.93; −4.68 | 0.005 |
| SDNN (ms) | 49.6 ± 17.3 | 47.4 ± 17.4 | −1.70 | 0.123 | 0.989 | 2.19 ± 1.38 | 4.88; −0.50 | 0.055 |
| pNN50 (%) | 16.2 ± 14.3 | 11.5 ± 13.4 | −27.0 | 0.327 | - | 4.64 ± 4.58 | 13.6; −4.33 | 0.648 |
| RMSSD (ms) | 35.8 ± 15.9 | 31.0 ± 16.2 | −7.34 | 0.292 | 0.944 | 4.80 ± 2.48 | 9.65; −0.060 | 0.145 |
| LF (ms2) | 593 ± 606 | 566 ± 575 | 0.64 | 0.0436 | - | 26.4 ± 45.2 | 115; −62.3 | 0.153 |
| HF (ms2) | 462 ± 443 | 350 ± 398 | −17.1 | 0.2581 | - | 111 ± 68.7 | 246; −23.4 | 0.331 |
| SD1 (ms) | 25.4 ± 11.3 | 21.9 ± 11.4 | −7.34 | 0.292 | 0.944 | 3.40 ± 1.75 | 6.84; −0.04 | 0.145 |
| SD2 (ms) | 65.1 ± 22.7 | 63.1 ± 23 | −1.00 | 0.088 | 0.994 | 2.04 ± 1.38 | 4.74; −0.67 | 0.042 |