Table 3 Descriptive characteristics during adolescence and young adulthood by sex¹

Adolescence

n = 53

n = 72

n = 125

 Biologic age² (year)

0.2 ± 1.7

−0.1 ± 1.8

0.0 ± 1.7

 Age (year)

12.0 ± 1.8

13.2 ± 1.8*

12.7 ± 1.9

 Age of PHV (year)

11.8 ± 0.8

13.2 ± 0.9

12.6 ± 1.2

 Physical activity (score)

2.9 ± 0.7

3.0 ± 0.6

3.0 ± 0.7

 Total energy intake (kcal/d)

1714 ± 461

1978 ± 615*

1867 ± 569

 Height (cm)

153 ± 11

162 ± 14**

158 ± 13

 Weight (kg)

46.0 ± 14

52.4 ± 14*

49.8 ± 14

 TBBMC (g)

1402 ± 452

1751 ± 612**

1604 ± 575

 TBaBMD (g/cm²)

0.87 ± 0.10

0.94 ± 0.12*

0.91 ± 0.11

 FNBMC (g)

3.3 ± 0.8

4.1 ± 1.0**

3.8 ± 1.0

 FNaBMD (g/cm²)

0.73 ± 0.13

0.81 ± 0.13*

0.77 ± 0.13

 LSBMC (g)

35.8 ± 13.4

40.8 ± 16.0

38.7 ± 15.1

 LAaBMD (g/cm²)

0.76 ± 0.15

0.75 ± 0.14

0.76 ± 0.14

Young adulthood

n = 51

n = 64

n = 115

 Biologic age² (year)

16.1 ± 3.5

15.0 ± 3.3

15.5 ± 3.4

 Age (year)

27.9 ± 3.4

28.3 ± 3.4

28.2 ± 3.4

 Physical activity (score)

2.3 ± 0.6

2.3 ± 0.7

2.3 ± 0.6

 Total energy intake (kcal/d)

1823 ± 698

2823 ± 1235**

2401 ± 1151

 Height (cm)

166 ± 7

179 ± 7**

174 ± 9

 Weight (kg)

70.7 ± 16

87.0 ± 14**

80.3 ± 16

 TBBMC (g)

2286 ± 321

3020 ± 413**

2706 ± 523

 TBaBMD (g/cm²)

1.12 ± 0.09

1.22 ± 0.10**

1.18 ± 0.11

 FNBMC (g)

4.3 ± 0.7

5.6 ± 0.8**

5.0 ± 0.9

 FNaBMD (g/cm²)

0.86 ± 0.10

0.95 ± 0.128**

0.91 ± 0.12

 LSBMC (g)

62.0 ± 12.6

76.2 ± 12.8**

70.3 ± 14.5

 LSaBMD (g/cm²)

1.04 ± 0.12

1.06 ± 0.12

1.05 ± 0.12