What neuroscientists have discovered in the past five years alone paints a riveting picture of the biological relationship between body, brain and mind. To keep our brains at peak performance, our bodies need to work hard. Physical activity is crucial to the way we think and feel. It cues the building blocks of learning in the brain; it affects mood, anxiety, and attention; it guards against stress and reverses some of the effects of aging in the brain.
— John J. Ratey, MD