Body mass index and cardiorespiratory fitness in 10-year-old English children in 1998 and 2008
| Boys | Girls | |||||
| 1998 | 2008 | p Value | 1998 | 2008 | p Value | |
| n = | 158 | 145 | 158 | 157 | ||
| Mean (SD) Age (years) | 10.4 (0.3) | 10.4 (0.3) | 10.5 (0.3) | 10.4 (0.3) | ||
| Mean (SD) BMI (kg/m2) | 17.6 (3.0) | 18.3 (3.1) | 18.6 (3.5) | 18.4 (2.6) | ||
| Mean (SD) BMI (z score)* | 0.32 (1.28) | 0.65 (1.16) | 0.02 | 0.48 (1.21) | 0.37 (1.02) | 0.4 |
| Median (IQR) 20mSRT† | 60 (43 to 75) | 40 (23 to 58) | <0.001 | 46 (37 to 56) | 29 (21 to 43) | <0.001 |
| Mean (SD) 20mSRT (km/h)* | 11.6 (0.9) | 10.8 (1.2) | <0.001 | 11.1 (0.7) | 10.2 (0.9) | <0.001 |
*p Values for independent t test; †p value for Mann-Whitney U test. BMI, body mass index; 20mSRT, 20 m shuttle-run test; BMI z scores are calculated based on the UK 1990 reference data.