Objective: This study was aimed at examining the trends and correlates of physical activity (PA) and sedentary behaviors among Chinese children. Methods: A total of 4,341 subjects (6,936 observations) aged 6-17 years who participated in the China Health and Nutrition Survey (2004-2015) were included. Of the subjects, 41% participated in the survey twice or more. Random-effects ordinal regression models and repeated-measures mixed-effects models were used to examine the PA trends. Quantile regression models were applied to examine the factors influencing PA and sedentary behaviors. Results: From 2004 to 2015, the prevalence of physical inactivity among Chinese children aged 6-17 years increased by 5.5% [odds ratio ( Conclusions A declining PA trend among Chinese children aged 6-17 years was observed from 2004 to 2015, and certain subgroups and geographical areas are at higher risk of physical inactivity.
Adolescent ; Asian Continental Ancestry Group/statistics & numerical data* ; Child ; Child Behavior/ethnology* ; China/epidemiology* ; Exercise ; Female ; Humans ; Male ; Nutrition Surveys ; Regression Analysis ; Sedentary Behavior/ethnology*

OBJECTIVE: To verify the association between sleep duration and television time with cardiometabolic risk and the moderating role of age, gender, and skin color/ethnicity in this relationship among adolescents. METHODS: Cross-sectional study with 1411 adolescents (800 girls) aged 10 to 17 years. Television time, sleep duration, age, gender, and skin color/ethnicity were obtained by self-reported questionnaire. Cardiometabolic risk was evaluated using the continuous metabolic risk score, by the sum of the standard z-score values for each risk factor: high-density lipoprotein cholesterol, triglycerides, glycemia, cardiorespiratory fitness, systolic blood pressure, and waist circumference. Generalized linear regression models were used. RESULTS: There was an association between television time and cardiometabolic risk (β, 0.002; 95% CI, 0.001; 0.003). Short sleep duration (β, 0.422; 95% CI, 0.012; 0.833) was positively associated with cardiometabolic risk. Additionally, age moderated the relationship between television time and cardiometabolic risk (β, - 0.009; 95% CI, - 0.002; - 0.001), suggesting that this relationship was stronger at ages 11 and 13 years (β, 0.004; 95% CI, 0.001; 0.006) compared to 13 to 15 years (β, 0.002; 95% CI, 0.001; 0.004). No association was found in older adolescents (β, 0.001; 95% CI, - 0.002; 0.002). CONCLUSIONS Television time and sleep duration are associated with cardiometabolic risk; adolescents with short sleep have higher cardiometabolic risk. In addition, age plays a moderating role in the relationship between TV time and cardiometabolic risk, indicating that in younger adolescents the relationship is stronger compared to older ones.
Age Factors ; Brazil ; epidemiology ; Cardiovascular Diseases ; epidemiology ; ethnology ; etiology ; Cross-Sectional Studies ; Metabolic Syndrome ; epidemiology ; ethnology ; etiology ; Prevalence ; Risk Factors ; Sedentary Behavior ; ethnology ; Sex Factors ; Sleep ; Television ; statistics & numerical data