Can Muscles Turn into Fat?

What kind of shape are you in? Do you have a rippling six-pack or a wobbling keg?

Most us try and stay in good shape but it's easy to be busy, feel tired and let exercise fall to the bottom of the priority pile. So what happens to that hard-earned body if you stop pumping the iron? If you don't move it, will you really lose it?

We've all seen it, or we think we've seen it. Top athletes or dedicated gym junkies stop training and all the bits that used to be buffed soon look stuffed.

Tony D'Agosto, a former amateur body builder who's given it away, is a case in point: "I was very happy with my body, it was lean, very athletic, it was in good shape, felt really good … the diet was so hard but the look was something I really appreciated. I really enjoyed it."

But then Tony decided that starting a family was his priority and he stopped working out. But his appetite didn't stop: "Pizza was my favourite — I really couldn't wait to get a pizza, I definitely enjoy eating a whole pizza. I'd probably get to the point I'd make myself sick I'd eat that much."

So should we all be worried about this? Could it happen to you?

Time to lay this one to rest and Associate Professor Gordon Lynch, an expert in muscle physiology at the University of Melbourne, can give us the answers.

What about this notion that muscle can turn to fat? Do you go along with that?
Associate Professor Lynch: I completely reject it. Muscle is one type of tissue and fat is a completely other type of tissue.
Here's what Associate Professor Lynch means — muscle can't turn into fat because they're two different things. Muscle is designed to contract, pulling on tendons, which move our bones and give our bodies movement. Fat on the other hand, is the body's way of storing energy. The less energy we use, the more fat we store, ready for when we need it.

So what happens when you stop exercising?
"When we're exercising heavily, we're working our muscles hard, we're eating a lot of food usually to fuel those workouts. If we stop exercising and we're still eating the same amount of food, quite naturally the energy balance between energy in, as food, and energy out, as exercise, or energy expenditure, changes. And so the idea is the balance shifts towards increasing body fat," says Associate Professor Lynch.

So that's it — stop exercising and keep eating as much and on goes the fat. The best solution is to keep exercising because there are benefits to having lean muscle if you want to keep your independence as you get older.
"Regardless of age, you can still maintain muscle perform the task of daily living we need to have muscle strength," says Associate Professor Lynch.

If you want muscles at 67 or 77 then you'll need to do weights and get protein from vegies, fish and lean meat, and lay off the junk food.
So that's why Tony turned to fat — too much junk food. But he's turned that around and though he'll never be an Arnold Schwarzenegger look-alike again, he's now a personal trainer and keeping his muscle mass up.


So if you don't use it you really will lose it. Your muscles can't turn to fat but you will pile on the pounds if you stop working out.

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