Importance, unique aspects and guidelines, and building blocks of early childhood physical activity from a socioecological perspective.

Although the benefits of physical activity are established across all age groups, researchers have recently noted that there is uncertainty as to which correlates and determinants of physical activity contribute to well-informed interventions and policies, particularly for the time frame of early childhood. The following narrative review highlights salient factors related to physical activity during early childhood, particularly in the United States, with respect to a socioecological framework. Discussion of factors at the individual (demographic, genetic), interpersonal (family support and perceptions of competence), organizational (e.g., preschool attended, preschool quality, teacher characteristics), community (availability, use, and perceptions of play spaces), and policy levels is included. While researchers often work within a public health framework that focuses on moderate-to-vigorous physical activity, or total (light-to-vigorous) physical activity, this may not fully align with how young children move. The importance of structured and unstructured play, risky play, and nature-based play are highlighted. Implications for basic and applied scientists, clinicians, and practitioners are addressed. Suggestions for future work include consideration of the context of physical activity, associations with other health behaviors, and further examination of the interpersonal and community level factors.