Excercise Strengthens Brain Cells

New studies have shown that exercise increases the number of mitochondria in the brain. The mice who exercised frequently showed increased growth of mitochondria after 8 weeks. Sedentary mice did not. Increase mitochondria in brain cells makes them healthier and may help protect against Alzheimer's and Parkinson's.
http://well.blogs.nytimes.com/2011/09/28/how-exercise-can-strengthen-the-brain/?ref=biologyandbiochemistry