"Physical fitness is not only 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." 
                                    -President John. F Kennedy 

This quote means that being healthy is good. Sometimes we think that just by having a nice body we are healthy which is wrong. Being healthy is maintaining a good body weight but also having a good healthy mind. The way we view things. Always stay positive. The more positive you stay the better things that will happen to you.