''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.''- John F. Kennedy


     What i think this quote means  is that the body and mind dont work as good as it should when the body is physically fit.  When the body is fit the mind is able to work at its best at the highest skill.