Walking

"In order to assure a certain progress in this reading, consider what hours you have free from the school and the exercises of the school. Give about two of them, every day, to exercise; for health must not be sacrificed to learning. A strong body makes the mind strong...

Never think of taking a book with you. The object of walking is to relax the mind. You should therefore not permit yourself even to think while you walk; but divert your attention by the objects surrounding you. Walking is the best possible exercise. Habituate yourself to walk very far."

-Thomas Jefferson

Third President of the United States of America (1743 to 1826)