Basic characteristics in male and female athletes at baseline, first and second follow-up
| Baseline 12 years old | First follow-up 15 years old | Second follow-up 18 years old | ||||
| Male | Female | Male | Female | Male | Female | |
| (n=48) | (n=28) | (n=34) | (n=14) | (n=23) | (n=11) | |
| Age, years | 12.1±0.2 | 12.1±0.2 | 15.3±0.3 | 15.2±0.2 | 18.4±0.3 | 18.3±0.2 |
| Height, cm | 151±7 | 154±7 | 174±10 | 170±9 | 184±8 | 171±7* |
| Weight, kg | 40±5 | 42±6 | 59±9 | 56±7 | 74±8 | 65±10* |
| BSA, m² | 1.3±0.1 | 1.4±0.1 | 1.7±0.2 | 1.6±0.1 | 2.0±0.1 | 1.8±0.1* |
| BMI, kg/m² | 17.4±1.5 | 17.6±1.7 | 19.4±1.7 | 19.4±1.9 | 21.6±1.6 | 22.1±3.1 |
| Resting HR, bpm | 71±12 | 72±11 | 61±9 | 64±10 | 54±9 | 58±8 |
| Exercise, hour/wk | 7.1±2.5 | 6.9±2.1 | 10.0±3.7 | 9.0±4.1 | 11.9±4.3 | 11.1±3.6 |
| Endurance exercise hour/wk | NA | NA | 5.7±3.5 | 4.9±2.6 | 8.0±5.1 | 6.6±3.0 |
| Cardiopulmonary exercise test parameters | ||||||
| VO2 max mL/min | 2545±336 | 2583±330 | 3704±626 | 2931±388* | 4906±695 | 3399±416* |
| VO2 max indexed, mL/min/kg | 65.1±6.3 | 57.9±4.9* | 64.2±5.7 | 52.4±6.0* | 67.1±6.7 | 52.9±5.0* |
| RER | 1.05±0.05 | 1.08±0.05* | 1.10±0.05 | 1.12±0.09 | 1.11±0.05 | 1.13±0.07 |
Observed values expressed as mean±SD. P values for baseline values are calculated using the Student's t-test. P values for follow-ups by linear mixed model regression analysis.
*Significant difference between male and female group, p≤0.01.
BMI, body mass index; bpm, beats per minute; BSA, body surface area; HR, heart rate; NA, not available; RER, peak respiratory exchange ratio; VO2 max, maximal oxygen uptake per minute.