Table 1 Descriptive characteristics of sample (average and [range])

Age (year)

14.0 [8 – 22]

13.6 [8 – 22]

Spinal BMC^a (g)

46.4 [16.2 – 100.1]

43.5 [13.2 – 85.6]

Femoral BMC^a (g)

31.7 [9.3 – 67.2]

24.9 [55.7 – 7.54]

BMI^b (kg/m ² )

22.0 [12.8 – 54.4]

22.5 [12.4 – 50.4]

Sedentary time (%)

52.6 [21.2 – 90.6]*

55.1 [14.8 – 79.1]*

MVPA^c (%)

23.2 [0.0 – 51.0]*

20.4 [0.0 – 74.0]*

TV watching (hours/day)

3.3 [1 – 6]

3.2 [1 – 6]

Computer use (hours/day)

2.3 [0 – 6]*

2.0 [0 – 6]*

Frequency of vigorous playing/exercising (number per week)

6.1 [0 – 21]*

5.4 [0 – 21]*

Frequency of strengthening activities (number per month)

11.5 [0 – 180]*

7.0 [0 – 60]*