Fitter bodies, fitter brains
Is the structure and function of the brain different in fitter people compared to less fit individuals? The short answer is yes, there is established research that supports the idea that regular physical activity is responsible for important structural changes in the brain, and this can be seen in people who have different physical fitness levels.
Regular physical activity affects brain function at the cellular, systemic and behavioural levels. Physical activity is critical for healthy brain development, which can lead to better academic and learning outcomes in children. For example, children who are active for as little as 20 minutes a day have better test scores1, attention and more active brains overall compared to less physically active children. Physical activity benefits to cognitive development are apparent from the very beginning of life (e.g. birth through to 5 years of age) . It has been shown that not moving enough negatively influences brain health, counteracting the benefits you would normally see when performing physical activity .
Indeed, not all sedentary time is created equal; a recent systematic review found that although reading is beneficial to cognitive development in early childhood (i.e. birth to age 5 years) screen time is not .
We know that physical activity increases blood oxygen saturation and angiogenesis in brain areas that are responsible for task performance. More specifically, the positive effects of physical activity on prefrontal cortex and hippocampus brain areas have been observed in several studies . Even the molecular architecture and behaviour of the basal ganglia has been implicated to be directly influenced by physical activity . In a recent meta-analysis on children’s physical activity, academic performance and cognitive function it was found that 13 out of 20 physical activity interventions had significant, positive effects on academic performance . There is indeed a strong mind-body connection, where fitter bodies create the environment for fitter brains to flourish .
FitBack’s authors and others have shown a positive relationship of cardiorespiratory fitness with behavioural and brain outcomes in young people. At a behavioural level, the different physical fitness tests (i.e., the ALPHA-fitness battery ) included in the FitBack project have shown to be positively related TO a better cognitive performance, better executive functioning, better intelligence and better academic performance . At a brain structural level, we have found that while cardiorespiratory is mainly related to grey matter (i.e., total and regional cortical and subcortical volume, and cortical thickness) , muscular strength is selectively related to white matter volume and integrity) . In addition, cardiorespiratory fitness is related to resting-state functional connectivity between hippocampal subregions and frontal regions .
To sum up, children with higher fitness level have healthier brains. This has been simply illustrated by a study from the ActiveBrains projects that has shown for first time that fitter children have larger brains, as in the following infographic.