
The body as an engine
Up to now you may have thought of fitness or looking good as simply losing weight. Or more specifically, losing fat. Everyone knows if you want to lose fat, the key to doing so is down to diet and exercise. Fat is one of the two important energy storage supplies that the body has access to, and by limiting the amount of food you eat, you give the body less raw material to turn into fat; likewise, exercising burns up more fat than being sedantry. You could even write it down as a formula: $$\partial fat = calories - exercise$$...

