Tricks to Maintain Muscle Mass on a Fast

Thomas DeLauer

You don't have to lose muscle mass while fasting. Here are Thomas's tips to make sure you maintain your gains.

Scroll down to read a transcript of this video. 


You're fasting, so you're going to lose all your muscle, right? Wrong. That is totally not the truth.

When you're fasting, your body produces what are called ketones, which preserve muscle. It's a natural protective process. Think about it like this. Your body's not going to waste away. Something that is metabolically active and needed. Okay? It's going to do whatever it can to preserve it. 

Normally when you're losing weight, your metabolism is going to slow down, but when ketones are present, it helps protect the body so the metabolism doesn't slow down. The reason that it does this is because it's preserving muscle. See, it's called beta hydroxybutyrate, and what it does is it spares a specific amino acid called leucine. If you've ever heard of branch chain amino acids before, the primary constituent of branch chain amino acids is leucine, and leucine is largely the amino acid that builds and preserves muscle. Normally when we're in a calorie deprived state, we oxidize leucine. And what that means is we burn it up, we use it, we use it for fuel, which means that, well, we're taking away from our muscles. So if you were to just go on a regular calorie restriction diet, there's a good chance you would lose some muscle, but crossing that clear line into a state of fasting or ultimately ketosis, you do your body a very good service by providing it with a fuel so it doesn't have to burn the leucine. Consequently, you preserve more muscle. 

Now let's talk a little bit about building muscle with your fasting regimen. Sure. you're not going to literally build muscle while you are in your fast. Yes, you need calories to come in to rebuild, but remember, it's all about timing. What we're trying to do is capitalize on the periods of time when we do eat so the body can take those nutrients in, build muscle, and make you happy that way.

So when you look at the period of a fast, I want you to view it as the staging area. You're setting the course. You're making it so that your cells are more insulin sensitive and more receptive to the fuel that you do take in after your fast. One of the things that I like to do is orient my workout towards the end of my fast. What that does for me is it allows me to capitalize on the insulin sensitivity after the workout, but also at the end of the fast. 

The simplest way to explain it like this: your cells are like sponges and the longer that you fast, the longer that you squeeze the sponge, the more it's going to absorb when you break your fast or let go of the sponge. So if you hold that sponge for a long period of time and then work out, you're going to absorb a lot more nutrients that are going to effectively help you repair and recover from said workout, consequently building more muscle tissue and helping you reach your goals a little bit faster. But the added side effect is you burn fat in the process too. And who doesn't want to build muscle and burn fat at the same time? 

Now you might be thinking that it sounds impossible to burn fat and build muscle at the same time because the common school of thought is that you have to go through a natural bulking phase where you eat a lot of calories and a cutting phase. Then you just have to have that clear line in between the two. Well think of your fasting regimen as sort of a miniature bulk and cut, right? You have your cutting phase during your fasting period where you're abstaining from calories altogether and your body has no choice but to burn fat, and then you have your blocking phase during the period of time in which you're eating or your body just absorbs the most amount of it.

The largest difference between this miniature bulk-and-cut and a traditional bulk-and-cut is that your damage is mitigated much more with this miniature bulk-and-cut, meaning the extra calories that you consume at the end of your fast are much less likely to cause a bunch of fat storage is if you were to go on a three month long binge eating a lot of food to try to build muscle. 

So let's summarize. Because of the presence of the ketone bodies, you're going to preserve much more muscle during your fast. And secondly, because you're insulin sensitive, you're going to be able to capitalize on the food that you do consume at the end of the fast. And the third thing that I want you to remember is as long as you are consuming enough calories at the end of the week, not day over day, you're going to probably gain some weight and build some muscle. Just lean on the science of the miniature bulk and the miniature cut. Personally, I fast a lot and I think it's working.

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