Purpose To quantitatively synthesize published evidence on the association between 24-hour movement behavior composition with adiposity in children and adolescents aged 3–18 years.

Methods Systematic literature searches were conducted in five electronic databases to identify papers published between January 2015 and January 2024. A machine learning-assisted systematic review was conducted to identify studies applying compositional data analysis to examine the association between 24-hour movement behaviors and adiposity in children and youth. Random effect meta-analyses were estimated to examine the relative association between each component of the 24-hour movement behavior composition and body mass index z-score (zBMI), waist circumference, fat mass percentage, and fat mass index (FMI).

Results A total of 16 studies reporting on 15,230 children and youth were included in the review. Most studies reported on zBMI (k = 14), followed by waist circumference (k = 5), body fat percentage (k = 3), and FMI (k = 2). Spending more time sleeping and engaged in moderate-to-vigorous intensity physical activity (MVPA) relative to other behaviors was associated with lower adiposity, while spending more time sedentary and engaged in light-intensity physical activity was associated with higher adiposity.

Conclusion These results provide support for most recommendations of the 24-hour movement behavior guidelines, including getting an adequate amount of sleep, limiting sedentary time, and engaging in MVPA, to improve adiposity outcomes.