Table 1 Characteristics of the participants by sex and age group (N = 1824)
| Â | 9-yrs | 15-yrs | ||
|---|---|---|---|---|
| Â | Girls | Boys | Girls | Boys |
N | 525 | 602 | 359 | 338 |
Height (cm) | 138.4 (7.0) | 139.9 (6.2) | 165.6 (6.5) | 175.7 (7.1) |
Weight (kg) | 34.0 (7.1) | 33.9 (6.3) | 57.9 (8.7) | 65.2 (12.8) |
Body Mass Index (kg/m2) | 17.6 (2.7) | 17.2 (2.4) | 21.1 (2.8) | 21.1 (3.7) |
Physical activity (PA) | Â | Â | Â | Â |
   Days of PA assessment | 3.6 (0.6) | 3.7 (0.6) | 3.4 (0.8) | 3.3 (0.8) |
   Total PAa (min/day) | 759 (59) | 769 (61) | 779 (77) | 778 (80) |
   Mean PA (counts/min) | 693 (251) | 796 (281) | 487 (167) | 542 (199) |
   MVPA (min/day) | 76 (23) | 95 (31) | 62 (25) | 68 (28) |
Season, N (%)b | Â | Â | Â | Â |
   Winter | 74 (14) | 88 (15) | 110 (31) | 115 (34) |
   Spring | 248 (47) | 304 (50) | 83 (23) | 92 (27) |
   Fall | 203 (39) | 210 (35) | 166 (46) | 131 (39) |