This from The Conversation:

We all know that exercise is good for our bodies, but current research is revealing that it is also good for our brains. Exercise has been shown to boost executive functions such as planning, working memory and multi-tasking.

In a study published in the journal Lancet Neurology, researchers at the University of Cambridge report that people who take part in intense exercise for an hour or more every week are far less likely to develop dementia. Their risk is reduced to nearly half that of others.

Source: How a memory boost from exercising could pass on to your baby – TheConversation.