There can be many health related componats to fitness... As many have said there is Strength, agillity, speed, flexability,endurance. Being Physically Fit is a lifestyle, you can work out and get yuor blood pumping but if you go home and waste what you just did i would say its not really a lifestyle of being fit.. I mean you need carbs and protein but we need to eat them the right way.. Once we get all that we will have a healthy lifestyle. Working out and eating riht will come easier and you will get much stronger after you do it all the time... Practice makes Perfect!!