Associated Trends in Sedentary Behavior and BMI Among Chinese School Children and Adolescents in Seven Diverse Chinese Provinces.

Background: Overweight and obesity is becoming a public health concern in China. Objective: We examined associated trends in sedentary behavior and body mass index (BMI) among school children and adolescents from seven diverse Chinese provinces from 1997 to 2004. Method: Sequential multiple regressions were conducted with combined cross-sectional data derived from the China Health and Nutrition Survey ( N = 5,497) to assess relationships between sedentary behavior and BMI. Results: Between 1997 and 2004, the amount of time children (6- to 11-year-olds) spent engaging in sedentary behavior increased from 1.71 to 3.14 h/day ( p < 0.05), while the amount of time adolescents (12- to 18-year-olds) spent engaging in sedentary behavior increased from 1.71 to 3.50 h/day ( p < 0.05). Studying before and after school and watching TV/videos each accounted for about half the increase in sedentary behavior. Both watching TV/videos and studying before and after school were significantly and positively associated with BMI in males, but not in females. Conclusion: With the growing amount of time Chinese school children and adolescents study outside of school and watch TV/videos, Chinese youth are increasingly likely to become more overweight unless population-based prevention actions are taken. [ABSTRACT FROM AUTHOR]