"A number of research studies have identified a link between improved cognitive functioning and exercise in elderly people.  A 2004 study, for example, found that exercise did, in fact, improve the cognitive functioning of elderly people with cognitive impairments or dementia.  In an analysis of more than 30 years of data and 2,020 subjects, this study found that groups who exercised fared better in terms of mental acuity than those who did not exercise." - Lit

“Even ten minutes can change your brain,” says Harvard Medical School psychiatrist John Ratey, author of the book Spark: The Revolutionary New Science of Exercise and the Brain. According to Ratey, exercise increases the level of brain chemicals called growth factors. It is these growth factors that help make new brain cells and establish new connections between brain cells to help us learn. - Lit