Table 1.
Characteristics of the Growing Up Today Study II participants at baseline (2004) and 2-year mean changes (2004, 2006 and 2008)
| Boys (n 3279) | Girls (n 4022) | |||||
|---|---|---|---|---|---|---|
| Characteristic | Mean | sd | % | Mean | sd | % |
| Age, years | 13·3 | 1·8 | 13·4 | 1·8 | ||
| Non-Hispanic white, % | 96·3 | 96·4 | ||||
| Weight, kg | 54·0 | 16·2 | 50·9 | 12·5 | ||
| 2-year Δ Weight | 11·4 | 7·4 | 6·1 | 6·0 | ||
| BMI | 20·3 | 3·8 | 20·1 | 3·6 | ||
| 2-year Δ BMI | 1·4 | 2·2 | 1·2 | 2·2 | ||
| BMI percentile* | 58·6 | 29·1 | 54·9 | 27·6 | ||
| 2-year Δ BMI percentile | –1·1 | 17·8 | –0·2 | 16·4 | ||
| Height, cm | 158·8 | 14·3 | 155·5 | 10·5 | ||
| 2-year Δ Height | 10·4 | 7·5 | 4·70 | 6·0 | ||
| HAZ | 0·1 | 1·2 | –0·1 | 1·1 | ||
| 2-year Δ HAZ | 0·1 | 0·7 | 0·1 | 0·6 | ||
| Overweight/obese prevalence†, % | 24·6 | 17·3 | ||||
| 2-year Δ Overweight/obese prevalence | –2·3 | 34·7 | –1·6 | 31·0 | ||
| OJ intake, glasses/week | 2·6 | 3·4 | 2·2 | 3·0 | ||
| 2-year Δ OJ intake | 0·0 | 3·3 | –0·2 | 2·8 | ||
| Total energy intake, kJ/d | 9736 | 3016 | 8159 | 2657 | ||
| 2-year Δ Total energy intake | –19·5 | 2946 | –344 | 2473 | ||
| Total energy intake excluding OJ, kJ/d | 9602 | 2975 | 8046 | 2619 | ||
| 2-year Δ Total energy intake excl. OJ | –76·6 | 2904 | –333 | 2443 | ||
| Screen time‡, hrs/week | 23·9 | 16·2 | 19·4 | 14·4 | ||
| 2-year Δ Screen time | 0·4 | 17·4 | –1·1 | 14·3 | ||
| Physical activity§, MET-h/week | 92·1 | 66·5 | 69·4 | 51·3 | ||
| 2-year Δ Physical activity | –1·3 | 62·3 | –1·5 | 48·7 | ||
HAZ, height-for-age Z-score; OJ, orange juice; MET, metabolic equivalent of task.
Corresponds to the BMI-for-age percentile based on the US Centers for Disease Control and Prevention growth charts for children and teens ages 2 through 19 years.
Overweight/obese categorisation is based on the cut-offs defined by US Centers for Disease Control and Prevention (2016 update): BMI-for-age ≥ 85th percentile.
Including television, VCR/DVD videos, video games and computer/internet.
Total metabolic equivalents per week calculated by summing time spent participating in various sports, games and intentional exercise of moderate/vigorous intensity (not including activities with METS < 4 such as walking).