Optimal 24-h movement behaviors and longitudinal changes in adiposity: a compositional data analysis in school-aged children.

UNLABELLED: This study aims to identify optimal time-use behavior compositions for adiposity and examine the longitudinal associations between adherence to these optimal compositions and 1-year changes in adiposity. Three hundred sixty-four children aged 8 to 12 years were included at baseline, of whom 237 children were included in the longitudinal analysis. 24-h movement behaviors were measured by a 7-day continuous accelerometer recording combined with a sleep questionnaire. Adiposity indicators, including body mass index z-score (zBMI), waist-to-height ratio (WHtR), and percent body fat (BF%), were measured and combined to represent overall adiposity. Compositional regression models were used to identify optimal time-use behavior compositions. General linear models examined longitudinal associations between behaviors and 1-year changes in adiposity. Optimal time-use behavior compositions differed across zBMI, BF%, and WHtR. The optimal compositions for overall adiposity were 9.3 (7.7-11.0) h of sleep, 9.7 (9.3-10.2) h of SB, 3.2 (2.8-3.6) h of LPA, and 1.8 (1.0-2.5) h of MVPA. Compared with meeting the optimal compositions (all four behaviors), adherence to any single behavior was longitudinally associated with a greater increase in BF% (β = 4.040, P = 0.009), whereas no significant in zBMI or WHtR (P > 0.05).

CONCLUSION: Balanced time-use of 24-h movement behavior is longitudinally associated with favorable BF% in school-aged children. Public health strategies should promote balanced movement behaviors.

WHAT IS KNOWN: • The prevalence of obesity among children and adolescents has increased over recent decades. • The 24-h movement behavior framework has shifted the paradigm of pediatric health from isolated behavior to a holistic time-use perspective. However, empirical evidence regarding the optimal time-use behavior compositions for adiposity remains constrained.

WHAT IS NEW: • The optimal overall adiposity-related composition was 9.3 h/day of sleep, 9.7 h/day of sedentary behavior, 3.2 h/day for light physical activity, and 1.8 h/day of moderate-to-vigorous physical activity. • Longitudinally, children adhering to only one optimal behavior had a greater 1-year increase in percentage body fat than those adhering to all four optimal behaviors.