Table 3.
Characteristics of athletes according to the different serum 25-OH vitamin D concentrations (four subgroups)
| Serum 25- OH vitamin D concentrations | ||||
|---|---|---|---|---|
| < 20 ng/mL | ≥ 20– < 30 ng/mL | ≥ 30– < 50 ng/mL | ≥ 50 ng/mL | |
| (n = 10) | (n = 24) | (n = 61) | (n = 17) | |
| Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD | |
| Age (years) | 26.3 ± 7 | 27.8 ± 5.4 | 25.5 ± 5.1 | 25.6 ± 3.9 |
| Height (cm) | 192 ± 7 | 189 ± 8.4 | 189 ± 7.5 | 190 ± 6 |
| Weight (kg) | 93.8 ± 9.8 | 93.5 ± 11.8 | 91.5 ± 10.2 | 96.5 ± 11.1 |
| BMI (kg/m2) | 25.8 ± 1.36 | 26 ± 1.56 | 25.2 ± 1.72 | 26.5 ± 2.33 |
| PTH (ng/mL) | 48.8 ± 10.2 | 37.3 ± 17 | 34.1 ± 19 | 24.3 ± 12.8 a |
| Calcium (mmol/L) | 2.36 ± 0.1 | 2.3 ± 0.1 | 2.39 ± 0.08 | 2.4 ± 0.07 |
| Serum 25-OH vitamin D (ng/mL) | 14.6 ± 3.9 | 25.8 ± 2.7a | 38.6 ± 5.2a/b | 56.5 ± 5.2a/b/c |
| Maximal workload (W) | 295 ± 48 | 340 ± 74 | 351 ± 58a | 406 ± 30a/b |
| Maximal aerobic power (W/kg) | 3.18 ± 0.64 | 3.59 ± 0.71 | 3.85 ± 0.46a | 4.24 ± 0.36a/b |
| Maximum heart rate (bpm) | 175 ± 15 | 175 ± 17 | 176 ± 10 | 177 ± 10 |
| Maximum SBP (mmHg) | 183 ± 19 | 187 ± 19 | 193 ± 19.5 | 195 ± 26 |
| Maximum DBP (mmHg) | 86.7 ± 5.6 | 86.8 ± 7.4 | 86.8 ± 9.7 | 88.8 ± 11 |
| Resting heart rate (bpm) | 59.2 ± 10 | 58.2 ± 8 | 58.2 ± 10 | 59.3 ± 13.9 |
| Resting SBP (mmHg) | 120 ± 12 | 119 ± 12 | 119 ± 7.4 | 126 ± 9 |
| Resting DBP (mmHg) | 81.6 ± 5 | 79.4 ± 10.3 | 74.9 ± 6.2a | 74.1 ± 8.9a/b |
| SEP (points) | 73.2 ± 23.8 | 75.5 ± 20.1 | 78.6 ± 15 | 80.6 ± 28.5 |
See Additional file 1 for specific p values. Bold text signifies significant differences. Values are given as means ± standard deviation (SD) and as median with interquartile ranges (IQR)
BMI = body mass index; PTH = parathyroid hormone; SE p = sun exposure points (measured over the two weeks prior to examination; maximum 112 points)
aSignificant difference vs. concentrations of < 20 ng/mL (p < 0.05);
bSignificant difference vs. concentrations of ≥ 20- < 30 ng/mL (p < 0.05);
cSignificant difference vs. concentrations of ≥ 30- < 50 ng/mL (p < 0.05)