Table 3.
Changes in resting HRV measures for the CON, LEX, and HEX groups following 24 weeks of resistance training or a control period.
| Variable | CON (N = 12) | LEX (N = 13) | HEX (N = 15) |
|---|---|---|---|
| RR interval (ms) | |||
| Pre-training | 956.4 ± 32.0 | 899.7 ± 15.9 | 951.4 ± 35.9 |
| Post-training | 954.5 ± 24.8 | 903.6 ± 18.5 | 1001.7 ± 39.6 |
| RMSSD (Ln ms) | |||
| Pre-training | 3.05 ± 0.20 | 2.89 ± 0.14 | 3.24 ± 0.16 |
| Post-training | 3.00 ± 0.13 | 2.94 ± 0.13 | 3.37 ± 0.16 |
| Total power (Ln ms2) | |||
| Pre-training | 6.47 ± 0.25 | 6.22 ± 0.20 | 6.44 ± 0.25 |
| Post-training | 5.94 ± 0.23 | 6.18 ± 0.21 | 6.41 ± 0.24 |
| Low-frequency (nu, %) | |||
| Pre-training | 62.8 ± 5.8 | 57.5 ± 4.1 | 52.2 ± 5.2 |
| Post-training | 57.1 ± 5.2 | 54.6 ± 4.7 | 41.5 ± 4.2 |
| Low-frequency (Ln ms2) | |||
| Pre-training | 4.92 ± 0.31 | 4.55 ± 0.26 | 4.92 ± 0.26 |
| Post-training | 4.33 ± 0.28 | 4.51 ± 0.23 | 4.75 ± 0.31 |
| High-frequency (nu, %) | |||
| Pre-training | 37.1 ± 5.8 | 42.5 ± 4.1 | 47.8 ± 5.2 |
| Post-training | 42.9 ± 5.2 | 45.4 ± 4.7 | 58.5 ± 4.2 |
| High-frequency (Ln ms2) | |||
| Pre-training | 4.27 ± 0.37 | 4.22 ± 0.30 | 4.80 ± 0.34 |
| Post-training | 3.99 ± 0.27 | 4.27 ± 0.28 | 5.12 ± 0.29 ‡ |
| LH/HF (Ln ratio) | |||
| Pre-training | 0.64 ± 0.29 | 0.33 ± 0.18 | 0.12 ± 0.24 |
| Post-training | 0.34 ± 0.24 | 0.24 ± 0.22 | -0.37 ± 0.18 § |
Values are expressed as mean ± SEM. CON = control group; LEX = low–medium-intensity training group; HEX = high-intensity training group; RMSSD = root mean square SD; Ln = natural logarithm; LF/HF = low-frequency/high frequency; nu = normalized units. § p < 0.05, vs. pre-training; ‡ p < 0.05, vs. CON by analysis of covariance with pre-training level and age as covariates.