Can muscle turn into fat? It sure looks like it can, but the reality is it can’t. When you have tight and defined muscles and you quit working out with weights or exercising at all in some cases, it seems like your hard muscle turns to flab. Remember muscle and fat are two different entities and one can not turn into another. What happens is when you stop exercising your muscle fibers grow smaller while your fat cells grow larger. With exercise, your muscles make the fibers grow but when you stop exercising, they reduce in size. Likewise, your body’s fat cells can change in size depending on how much fat each one stores. So to keep your body fit, healthy and strong, keep up your exercise and don’t let conditioned muscles become flabby!