Physical Fitness is one of the most important key parts of a healthy life

"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. Intelligence and skills can only function at the peak of their capacity when the body is healthy and strong."  - John F Kennedy

I think this statement is about how you have to be physically strong to be mentally strong. And one of the most important key parts of that is by not doing drugs and staying out of them to have a healthy and strong body. When you are healthy you van perform at your best in school, work, or any activity that you are doing. For example if a person who does drugs goes to school then they have trouble concentrating but a healthy person will have no trouble concentrating on the task.