TABLE 1.
Description of physical fitness variables, bone outcomes and covariates of the sample used in phase 1 of the study (n: 160).
| Total | Boys (85) | Girls (75) | ||||
|---|---|---|---|---|---|---|
| X ± SD | X ± SD | X ± SD | ||||
| Age (years) | 8.9 ± 1.56 | 8.25 ± 1.65 | 8.35 ± 1.50 | |||
| Height (m) | 1.33 ± 0.10 | 1.34 ± 0.10 | 1.33 ± 0.11 | |||
| Weight (kg) | 33.03 ± 10.14 | 32.80 ± 9.31 | 33.29 ± 11.03 | |||
| Maturity-offset* | −3.02 ± 1.73 | −4.01 ± 1.11 | −1.95 ± 1.65 | |||
| TBF%* | 32.66 ± 8.53 | 30.47 ± 8.61 | 35.15 ± 7.77 | |||
| Sprint (s)* | 4.54 ± 0.85 | 4.45 ± 0.96 | 4.63 ± 0.70 | |||
| Agility (s)* | 7.91 ± 1.00 | 7.70 ± 1.01 | 8.13 ± 0.94 | |||
| Lower limb power (cm)* | 110.58 ± 24.04 | 117.09 ± 24.57 | 103.54 ± 21.48 | |||
| Upper limb power (cm)* | 184.23 ± 53.85 | 191.92 ± 51.83 | 175.90 ± 55.10 | |||
| n | % | n | % | n | % | |
|---|---|---|---|---|---|---|
| BMC TBLH | ||||||
| Normal bone mass | 135 | 85.4 | 77 | 91.6 | 59 | 78.7 |
| Risk for low bone mass | 23 | 14.6 | 7 | 8.4 | 16 | 21.3 |
| aBMD TBLH | ||||||
| Normal bone mass | 137 | 86.7 | 77 | 92.8 | 60 | 80.0 |
| Risk for low bone mass | 21 | 13.3 | 6 | 7.2 | 15 | 20.0 |
| BMC upper limbs and trunk | ||||||
| Normal bone mass | 134 | 84.3 | 74 | 88.1 | 60 | 80.0 |
| Risk for low bone mass | 21 | 15.7 | 10 | 11.9 | 15 | 20.0 |
| aBMD upper limbs and trunk | ||||||
| Normal bone mass | 124 | 78.0 | 67 | 79.8 | 57 | 76.0 |
| Risk for low bone mass | 35 | 22.0 | 17 | 20.2 | 18 | 24.0 |
| BMC total spine and pelvis | ||||||
| Normal bone mass | 130 | 81.3 | 73 | 85.9 | 57 | 76.0 |
| Risk for low bone mass | 30 | 18.8 | 12 | 14.1 | 18 | 24.0 |
| aBMD total spine and pelvis | ||||||
| Normal bone mass | 128 | 80.0 | 68 | 80.0 | 60 | 80.0 |
| Risk for low bone mass | 32 | 20.0 | 17 | 20.0 | 15 | 20.0 |
| BMC pelvis and lower limbs | ||||||
| Normal bone mass | 130 | 81.3 | 73 | 85.9 | 57 | 76.0 |
| Risk for low bone mass | 30 | 18.8 | 12 | 14.1 | 18 | 24.0 |
| aBMD pelvis and lower limbs | ||||||
| Normal bone mass | 124 | 77.5 | 67 | 78.8 | 57 | 76.0 |
| Risk for low bone mass | 36 | 22.5 | 18 | 21.2 | 18 | 24.0 |
| BMC upper limbs, trunk and pelvis | ||||||
| Normal bone mass | 129 | 81.1 | 72 | 85.7 | 57 | 76.0 |
| Risk for low bone mass | 30 | 18.9 | 12 | 14.3 | 18 | 24.0 |
| aBMD upper limbs, trunk and pelvis | ||||||
| Normal bone mass | 117 | 73.6 | 61 | 72.6 | 56 | 74.7 |
| Risk for low bone mass | 42 | 26.4 | 23 | 27.4 | 19 | 25.3 |
| BMC total spine, pelvis e lower limbs | ||||||
| Normal bone mass | 126 | 78.8 | 70 | 82.4 | 56 | 74.7 |
| Risk for low bone mass | 34 | 21.3 | 15 | 17.6 | 19 | 25.3 |
| aBMD total spine, pelvis e lower limbs | ||||||
| Normal bone mass | 121 | 75.6 | 66 | 77.6 | 55 | 73.3 |
| Risk for low bone mass | 39 | 24.4 | 19 | 22.4 | 20 | 26.7 |
*Denote a significant difference (p < 0.05). n: absolute value; X ± SD: average value and standard deviation; %: percentage value; TBF%: total body fat percentage; BMI: body mass index; BMC: bone mineral content; aBMD: areal bone mineral density; TBLH: total body less head.