24h movement behaviors and self-regulation in preschoolers: Cross-sectional associations using compositional and isotemporal analyses

Early childhood is a critical period for brain development, particularly in self-regulation (SR), which is essential for pre-academic success and socio-emotional competence. Recent studies highlight the role of 24-h movement behaviors (i.e., physical activity (PA), sedentary behavior (SB), and sleep) in SR. However, the relationship between the composition of these behaviors and SR remains unclear. This study aimed to analyze the association between the composition of 24-h movement behaviors and cognitive and behavioral SR in preschoolers; and to investigate predicted changes in SR when time in different behaviors is reallocated. The sample comprised 223 preschoolers (4–5 years-old) enrolled in public early childhood education centers in Petrolina, Brazil. Movement behaviors were assessed using accelerometry, sleep was evaluated by parent report, and cognitive and behavioral SR were measured using the Early Years Toolbox and the Head, Toes, Knees, Shoulders–Revised test, respectively. Compositional and isotemporal data analysis were used to examine the relationships between movement behaviors and SR, and time reallocations, respectively. The 24-h movement behaviors composition predicted 6 % of the variance in visuo-spatial working memory and cognitive flexibility; and 13 % in behavioral SR. Reallocating 5, 10 or 15 min from sleep and moderate-to-vigorous PA to light PA or SB was positively associated with behavioral SR, though no association has been seen on cognitive SR. These findings suggest a possible positive mechanism linking low-intense activities with children's behavioural SR, that should be further explored in longitudinal and interventional designs aimed at optimizing SR in early childhood.