A recent article in Frontiers of neuroscience (May 2018) has identified that exercise can help the brain repair itself. The researchers looked at the effect of the sedentary state on mice, compared to those who exercised. They found that the stem cells in the sedentary mouse brain became less active. Although there were expected changes in the muscle signalling pathways from motor deprivation, they also discovered that this effect, carried over into the brain. Also the mechanism for providing nutrients to neurons was also reduced.
The technical description of the effect was ‘the stem cells of the inactive mice, the gene Cdk5rap1 was less active’.
If you would like to read the article itself, please follow the link to: https://www.frontiersin.org/articles/10.3389/fnins.2018.00336/full
So in summary if you want a healthier brain, exercise will help.