Lifting myth: Once you stop training your muscles turn into fat


This is part of a series of posts by Jennifer (@liftingfairy on PumpUp), a bikini competitor. Check out her blog here. 

You may or may not have been told that once you stop exercising, your muscles turn into fat. But is this actually true? Sure, Arnold Schwarzenegger and Ronnie Coleman no longer have their former physiques, but are they really ‘fat’ 

I’ll admit that they don’t look that fit. Maybe a bit flabby. But it is scientifically impossible that their muscles turned into fat. Muscles and fat are two completely different substances. That’s like saying ’ I will turn my fat into muscles’ it just doesn’t work like that!

I will explain to you what actually happens.

Let’s take the example of a man who eats a lot of calories to his body the nutrients that it needs to build a certain amount of muscles. While he is still training, his muscles also allow him to burn more calories each day. This helps him to stay fairly lean. However, if he stops training— for whatever the reason might be—and maintains his former eating habits, his body will not only lose the extra calorie-burn from his workouts, but also the extra burn from his muscle mass.


Now you can say that he is going to turn into a little fluffy ball because if he keeps eating the same way, he will lose muscles and gain fat. But he won’t be turning his muscles into fat. That’s what people keep misunderstanding.

Muscles are breaking down because they are no longer needed. Your body will, however, gain fat, if you have the same caloric intake as before. But you won’t turn into a flabby ball if you take a little break from your sports. If you stop training you will certainly lose muscle tissue, but if you also reduce your caloric intake you won’t gain fat. 


According to a study, strength and muscle mass are generally maintained for up to 4 hours of no training. In my experience, I’ve seen drop-offs in my strength within seven days without training. However, I never experienced major muscle loss within two or even three weeks out of the gym.

If you are afraid of losing too much strength or muscle when you are on vacation, just do a full-body-core workout like push-ups, planks, pull-ups, squats, lunges or go for a run at the beach.

This is part of a series of posts by Jennifer, a bikini competitor from Luxembourg. Check out her blog and follow her on PumpUp @liftingfairy and on Instagram @lifting_fairy.