Isotemporal Substitution Effects of 24-hour Movement Behaviors on Executive Function in Preschool Children

ABSTRACT Objective This study aims to examine the relationship between 24-h movement behaviors (MBs) and executive function (EF) in preschool children. Methods A total of 266 preschool children participated in this study. Physical activity (PA) and sedentary behavior (SB) were measured using an accelerometer (ActiGraph GT3X-BT), sleep duration was assessed using sleep logs, and EF was evaluated using the Early Years Toolbox. Compositional data analysis was employed to explore associations among the three movement behaviors. Results (1) The relative distribution of 24-h MBs was significantly associated with inhibition, shifting, and updating (all p 10%. The explanatory power was the highest for inhibition (16.3%). (2) After adjusting for other MBs, SB was negatively associated with inhibition (γ12 = –0.11, p < 0.001), shifting (γ12 = –1.45, p = 0.001), and updating (γ12 = –0.58, p = 0.004). In contrast, sleep (SP) was positively associated with shifting (γ11 = 1.60, p = 0.020). (3) When 15 min/day of SB was isotemporally substituted with SP, inhibition scores increased by 0.003, and shifting scores increased by 0.064; conversely, replacing SP with SB resulted in a significant decline. Conclusion The relative distribution of 24-h MBs significantly predicted EF in preschool children. Among MBs, SB and SP were most strongly associated with EF. Shifting SB toward SP may effectively improve EF performance, particularly shifting ability.