People exercise for many reasons: to develop stamina, stimulate muscle growth or reinforce positive mental health. As it turns out, exercise may be also be important for strengthening important regions of the brain best known as white matter.
White matter is primarily responsible for carrying nerve signals from one brain region to another, and tracts of white matter in the brains of children who are physically fit differ from those of their less active peers. In children who are considered fit, white matter appears more compact, a characteristic associated with faster and more efficient nerve activity, a new study has found.
While other studies have linked exercise with changes in certain brain regions, this study is an important first look at white matter specifically. It was already clear that children with higher levels of aerobic fitness have more gray matter volumes. These are brain regions important for memory and learning.
The differences in the characteristics of several white matter tracts based on the child’s physical fitness were significant, and all of them have been found to play a role in attention and memory.
The team used a form of magnetic resonance imaging (MRI) to look at tracts of white matter in the brains of 9- and 10-year-old children. This enabled them to determine how fibrous and compact the tissue appears.
Researchers made sure the children in the fit and not-fit groups were equal in terms of variables such as IQ, learning disabilities or onset of puberty, so these did not affect the results.
The differences in the characteristics of several white matter tracts based on the child’s physical fitness were significant, and all of them have been found to play a role in attention and memory, according to Chaddock-Heyman.
Past work has also demonstrated a link between fitness and gains on certain mental abilities among older adults and in academic settings, suggesting that exercise exerts its beneficial effects on white matter throughout the lifespan.
The new findings add to a growing body of evidence that suggests exercise can change the brain in ways that improve cognitive function, and offer some useful details about why it is that children who are fit do better than their lower-fit peers on cognitive tasks and in the classroom.
The study is published in Frontiers in Human Neuroscience.