Temporal trends in physical fitness among Chinese children and adolescents from 2000 to 2019 and analysis of social-ecological factors.

This study aimed to estimate temporal trends in physical fitness (PF) by regions, age groups and nutritional status among Chinese children and adolescents and to longitudinally examine PF determinants based on social-ecological model. Participants (n = 68,265) aged 7-18 were from five successive national surveys (2000 to 2019). Six tested items of PF were calculated as PF indicator (PFI), which was used to divide participants into two categories: low vs. moderate/high. One-way analysis of variance was used to compare difference and change trend of PFI. Linear regression evaluated relationship between PFI and body mass index (BMI), and logistic regression assessed association between PFI and factors of behaviours and lifestyles on individual-, family- and school-level based on the social-ecological model. PFI declined sharply from 2000 to 2010, increased slightly from 2010 to 2014 and then edged down in 2019. Students with moderate BMI and students in urban areas tended to have higher PFI, and larger increase of PFI was found in students aged 7-9 and 13-15 after 2010. Several determinants on individual-, family- and school-level related to PFI. Efforts to develop PF mainly include increasing PA and reducing sedentary behaviours by facilitating home-school collaboration and emphasizing age-, region- and BMI-specific actions.

The association between various dimensions of sleep parameters and mental health: A large cross-sectional study of 13554 Chinese students.

OBJECTIVES: We aimed to investigate the association between multiple sleep variables and mental health among Chinese students aged 9-22. METHOD: We stratified the included 13,554 students by educational levels. Sleep parameters contained sleep duration on school days and weekends, napping time, chronotype and social jetlag (SJL), which were calculated via questionnaires. Individual psychological well-being and distress were assessed by Warwick-Edinburgh mental Well-being scale and the Kessler Psychological Distress Scale 10 respectively. The multiple linear and binary logistic regression were applied to analyze the association of sleep with mental health. RESULTS: Short sleep on school days showed significantly positive association with psychological problems. While among senior high school students, we found reverse result that sleeping less might negatively associated with more severe distress (7-8 h: aOR = 0.67, 95% CI: 0.46, 0.97). The association of sleep duration with mental health was attenuated a lot on weekends. The chronotype was significantly related with mental health in primary and junior high school: intermediate chronotype (vs late chronotype) was associated with greater wellbeing (ß = 1.03, 95% CI: 0.09, 1.96; ß = 1.89, 95% CI: 0.81, 2.97) and less distress (aOR = 0.78, 95% CI: 0.60, 1.00; aOR = 0.73, 95% CI: 0.58, 0.91). The relationship between SJL, napping duration and psychological health problems were also observed in some educational levels. CONCLUSION: Sleep deprivation on school days, late chronotype and SJL were positively associated with worse mental health in our study, which differed among various educational stages.

Associations of multiple sleep dimensions with overall and abdominal obesity among children and adolescents: a population-based cross-sectional study.

BACKGROUND: The relationship of insufficient sleep with the increased risk of obesity has been reported, but less is known about other sleep dimensions in the sleep-obesity associations. OBJECTIVES: To assess the associations of multiple sleep dimensions with overall and abdominal obesity among Chinese students. METHODS: This was a cross-sectional study involving 10,686 Han students aged 9-18 from Chinese National Survey on Students' Constitution and Health (CNSSCH). We collected sex, age, regions, parental educational levels, physical activity duration and sleep-related information by questionnaire survey, and also conducted anthropometric measurements including height, weight and waist circumference (WC). Unadjusted and adjusted binary logistic regression models were used to estimate the associations of sleep-related dimensions with obesity-related indicators. RESULTS: Short sleep duration was associated with higher body mass index (BMI), larger WC and higher waist-to-height ratio (WHtR) in 9-12 and 16-18 age groups, whereas prolonged sleep duration on weekday was associated with higher BMI in 13-15 age group. Non-habitual midday napping and midday napping ≤0.5 h/d (vs 0.5 to 1 h/d) increased the risk of higher BMI in 13-15 age group, and the former was also associated with larger WC in 9-12 age group. Late bedtime was associated with larger WC and higher WHtR in 9-12 age group and with higher BMI and WHtR in 13-15 age group. Students aged 9-12 with social jet lag ≥2 h were found to have greater BMI after adjustment (Odds Ratio: 1.421; 95% confidence interval: 1.066-1.894). CONCLUSIONS: Short or overlong sleep duration, late bedtime and great social jet lag were associated with higher prevalence of overall or abdominal obesity, while moderate midday napping can effectively decrease the risk. Those findings may assist in developing preventive strategies to combat obesity epidemic.

Trends of overweight and obesity prevalence in school-aged children among Henan Province from 2000 to 2019.

Objectives: Overweight and obesity are harmful to human health. However, the latest trends of Chinese childhood overweight and obesity prevalence are not available. The aim of this study was to examine the trends from 2000 to 2019 among students in China. Methods: We analyzed data of 66,072 students in the Chinese National Survey on Students' Constitution and Health from 2000 to 2019. Overweight and obesity were defined based on the standard formulated by the International Obesity Task Force (IOTF standard), the World Health Organization (WHO standard), and the Working Group on Obesity in China (WGOC standard), respectively. The χ2-test was used to test the trends of overweight and obesity prevalence and logistic regression was conducted to evaluate the prevalence odds ratios of boys vs. girls and urban vs. rural areas. Results: The prevalence of obesity/overweight and obesity combined was 6.03/23.58% (IOTF standard), 10.56/25.88% (WGOC standard) and 10.75/29.69% (WHO standard) in 2019. From 2000 to 2019, according to the WGOC standard, the prevalence increased from 2.51 to 10.56% for obesity and increased from 9.81 to 25.88% for overweight and obesity combined (P for trend < 0.001). Obesity/overweight and obesity were greater problems in boys than girls and urban than rural areas, but urban-rural differences decreased over time. Conclusion: Overweight and obesity prevalence increased significantly in children and adolescents in China from 2000 to 2019. The prevalence of overweight and obesity in rural areas may contribute to a large percentage of children with overweight and obesity.

Physical fitness among middle school students in Henan Province and associated factors / 中国学校卫生

Objective@#To understand physical fitness among students aged 13-18 years in Henan Province and its influencing factors.@*Methods@#Data of 21 785 students aged 13-18 years who participated in the national physical fitness surveys in Henan Province in 2014 were analyzed based on phyical fitness indicators and the questionnarie of physical exercise. The qualified rates of physical fitness indicators were evaluated based on the "National Students Constitutional Health Standards"(2014 revised edition).@*Results@#In 2014, the eligible rate for physical test was 85.6% for boys and 82.5% for girls. Higher eligible rate was observed among boys with sleep duration less than 7 hours, compared to those with higher than 7 hours, while lower eligible rate was more likely observed in boys who reported sweaty and tired in PE class(OR=0.76), sweay and extreme tired in PE class(OR=0.72). Higher eligible rate was more common among girls who attended exercise during recess 2-3 times per day (OR=1.18) compared to those attended exercises higher than 3 times per day. Lower eligible rate was more common among girls with sleep duration less than 7 hours (OR=0.88) and those with low attendance in school recess exercises(OR=0.77). Normal weight, living in urban area, sufficient and regular PE class, daily physical exercise for more than 1 hour, enjoying physical exercise and extracurricular sports activities or long-distance running activities have higher success rates(P<0.05).@*Conclusion@#There is a relatively high eligible rate of phyical fitness among middle school boys and girls in Henan Province. Physical fitness is related to multiple factors. These findings highlight the need to target physical fitness interventions with sufficient time allocation in PE class and physical activity so as to effectively promote the phyical quality of students.