“Physical fitness is not only one of the most important keys to a healthy body. It is the basis of dynamic and creative intellectual activity. The relationship between the soundness of the body and the activities of the mind is subtle and complex. Much is not yet understood. But we do know what the Greeks knew:that intelligence and skill can only function at the peak of their capacity when the body is healthy and strong.”
This quote is trying to say if your body feels good and is running correctly, your everyday life will be simple and easy going. If you feel good, you do good. Also fitness allows a person to relieve the stress that they build up in their everyday life. Its a key necessity in life, and a lot of people take it for granted everyday. As you are working out, your mind is becoming stronger because its beginning to realize the ability to do more things not able to do before.