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Physical Activity, Fitness, School Readiness, and Cognition in Early Childhood: A Systematic Review.

BACKGROUND
Early childhood is an important age for brain and cognitive development. Given the support of physical activity and fitness on cognition and academic performance in older children, more research has emerged recently focusing on younger children. In this systematic review, the authors review the relations between physical activity/fitness and academic-related (ie, school readiness and cognitive) outcomes in early childhood.


METHODS
A search was conducted from PubMed, PsycINFO, Web of Science, ERIC databases, and reference lists for articles that had participants aged less than 6 years were written in English, and were in peer-reviewed journals. Articles were excluded if the design was a case study or case series report. The Grading Recommendations Assessment, Development and Evaluation framework was followed to assess the quality of evidence by study design.


RESULTS
Sixty-eight articles reporting on 72 studies (29 observational and 43 experimental) were included. The majority of study effects were mixed, and the quality of evidence varied from very low to low.


CONCLUSIONS
A clear consensus about the role of physical activity and fitness on academic-related outcomes in early childhood is still lacking given the high heterogeneity in methodological approaches and overall effects. Additional high-quality studies are needed to determine what specific dosages of physical activity are impactful at this age.