Findings regarding the effects of regular physical activity on cognition in children have been inconsistent due to a number of demographic factors and experimental considerations. The present study was designed to examine baseline cognitive performance and executive function demands, as possible factors underlying the lack of consensus in the literature, by investigating the moderating role of those factors on the effects of physical activity on cognition. We reanalyzed data from three randomized controlled trials, in which the effects of regular physical activity intervention on cognition were examined using executive function tasks that included at least two task conditions requiring variable executive function demands, with a cumulative total of 292 participants (9-13 years). The results indicate that cognitive improvements resulting from physical activity intervention were greater in children with lower baseline cognitive performance. The main analysis revealed that beneficial effects of physical activity intervention on cognitive performance were generally observed across executive function conditions. However, secondary analyses indicated that these general effects were moderated by baseline performance, with disproportionately greater effects for task conditions with higher executive function demands. These findings suggest that baseline cognitive performance is an individual difference variable that moderates the beneficial effects of physical activity on executive functions.
Keywords: adolescent; cognitive control; executive functions; exercise; fitness.