Here is a book that you should add to your reading list. It will literally revolutionize your life. The title is Spark: The Revolutionary New Science of Exercise and the Brain and the author is Dr. John J. Ratey.
I know I won't do the book justice with a simple synopsis but you need to know that the evidence it mounting/overwhelming on the benefits of exercise and your mind (think mood, stress, and interestingly learning). Our CEO, Stewart Hughes, had recommended this book about a year ago. I didn't take notice (mainly because I had a number of other books I was reading at the time) until my wife started reading it and telling me some of the really cool things she was learning from this book. Thank goodness I listened my wife. I have rekindled my love for exercise and am making it a point to get out and be more active in some way each day. You can too!