Does a header a day keep the positive effects of physical activity on cognitive performance away? A call to consider physical activity-related head impacts as a moderator variable

Abstract There is growing evidence that acute and chronic physical activity (PA) can improve cognitive performance and that variables such as PA dosage and type are important moderators for this effect. Notably, some PA types (e.g., football/soccer) encompass events (e.g., headers) that might attenuate the positive effects of PA on cognitive performance, and this issue is not explicitly considered in some PA-type classification approaches (e.g., open- versus closed-skill PA). Thus, this article aims to move beyond the intuitive perspective that PA improves cognition by advocating that head impact, which is an integral part of specific PA types (e.g., football/soccer), should be considered as a moderator when investigating or developing theories on the influence of PA on cognitive health and performance. We propose that recognizing the moderating role of PA-related head impact will add a fruitful and nuanced understanding of dose–response relationships between PA and cognition and serve as a key prerequisite to achieving a better individualization of PA prescription.