Association between 24

The 24-hour movement behaviors, comprising physical activity, sedentary behavior, and sleep, are crucial factors affecting children's mental health. This study aims to explore the longitudinal association between 24-hour movement behaviors and psychological well-being in overweight and obese children, providing empirical evidence for mental health promotion in this population. A total of 445 overweight and obese children were recruited via stratified cluster random sampling from a provincial capital city in China and followed up for one year. Measures included objectively assessed physical activity and sleep duration using triaxial accelerometers (ActiGraph GT3X+), parent-reported sedentary screen-based time (SST), and self-reported psychological well-being. After one year, the proportion of children meeting all 3 movement guidelines increased from 10.11% to 11.68%, while those meeting none increased from 11.24% to 15.06%. After adjusting for relevant covariates, children who met individual guidelines for moderate-to-vigorous physical activity (MVPA) (β=0.377, 95% CI 0.209 to 0.545), sleep (β=0.187, 95% CI 0.042 to 0.332), or guideline combinations of MVPA+SST (β=0.545, 95% CI 0.377 to 0.713) and MVPA+sleep (β=0.602, 95% CI 0.449 to 0.755) showed significant improvements in psychological well-being after one year. Additionally, an increase in the number of guidelines met was significantly associated with improved well-being (β=0.113, 95% CI 0.011 to 0.214). Adherence to any single movement guideline, especially MVPA or sleep, and combinations such as MVPA+SST or MVPA+sleep is significantly associated with enhanced psychological well-being in overweight and obese children. Integrated behaviors may be an effective strategy to improve mental well-being in this population.