by Christian Thibaudeau
Are You Really Losing Muscle While Dieting?
You're probably not losing muscle when dieting, but it can happen. Here's why, plus some easy ways to lose fat, not muscle, while leaning up.
How Do I Lose Fat, Not Muscle?
First, don’t panic. It’s common for lifters to think they’re losing muscle when trying to get lean. This happens even if they’re doing everything right: tracking calories, keeping protein high, backing off training volume, and prioritizing the big lifts.
Let’s discuss the fear of losing muscle and why you can’t always trust it. Then I’ll get into the details on preventing catabolism (muscle loss) and what will cause it to actually occur.
Three Signs You’re Not Losing Muscle
Are you really losing muscle? Maybe not. Here are three things indicating that you’re actually keeping muscle and only losing fat:
- You’re maintaining your strength.
- You’re only losing a conservative amount of weight, indicating that the caloric restriction is not excessive.
- Your protein intake is sufficient for your size – at least a gram per pound of body weight.
Unless you’re under 10 percent body fat, it’s very unlikely that you’re losing muscle if you’re still training and eating sufficient protein, which would be around 1 to 1.25 grams per pound. (Yes, even in a caloric deficit.)
You might FEEL like you’re losing muscle. You might look smaller or deflated, but that comes from storing less glycogen and water inside your muscles. Glycogen is how your body stores carbs inside the muscles. It’s a combination of glucose (broken down carbs) and water.
You’ll store less glycogen if you’re cutting calories (and likely carbs). Why? Because you don’t have “extra energy” to store since you’re pretty much using it all.
If you store less glycogen and water, your muscles become flatter and smaller looking. A muscle with less glycogen/water is like a balloon with less air. That can mess with your mind, but it’s not muscle loss.
To build or maintain muscle, you need a growth stimulus, protein for muscle repair, and energy to fuel the building process. If you’re still training hard and eating sufficient protein, you should at least maintain muscle.
10 Percent Body Fat: The Cut Off Point
If you’re in a caloric deficit, don’t you lack the energy to build muscle? Not if you’re over 9 percent body fat. Above that, your body has plenty of stored energy to fuel the process without the risk of running out of stored fuel.
Once you get below 10 percent body fat, you may be unable to fuel the repair process since your body might want to preserve the little energy store it has for simple things, like survival.
But until you’re really lean, you shouldn’t lose muscle unless you REALLY consume an idiotic amount of calories.
Does Strength Loss Indicate Muscle Loss?
Not necessarily. It’s true, some people lose a little strength when they diet. But it’s rarely due to muscle loss. There are other reasons.
First, notice that the strength loss is mostly on multi-joint exercises. The bench press, military press, and squats are especially affected. This loss in “strength” doesn’t happen with isolation or machine exercises, and it often doesn’t affect pulling exercises.
It’s common to maintain or even increase strength on the triceps extension, pec deck, and dumbbell lateral raise, yet see your bench press (which requires the same muscles) go down.
Clearly, this isn’t due to muscle loss; otherwise, the isolation exercises would go down too. In fact, often, the free-weight bench press will go down, but pressing on a chest machine will stay up or even increase.
The reason? A decrease in passive stability. That’s when non-contractile elements stabilize a joint by increasing pressure. For example, if you blow up a muscle by storing more water, glycogen, and fat, that muscle becomes inflated and “packs” the joint more. This creates pressure which makes the joint more stable. Even body fat can contribute to passive stabilization and water retention.
Why is that important? Because if a joint is less stable, the body will protect itself by inhibiting force production – not allowing you to use all of your strength potential to avoid injuries. The more stable the body feels, the more of your strength it allows you to use.
That’s why it’s common for powerlifters to “bloat up” before a meet. They’ll eat a boatload of salty, high-carb food and drink tons of water to increase both glycogen and water retention. This increases passive stability and allows them to lift more weight.
Pressing movements are more affected because they’re more “dangerous” for the shoulder joint, the least stable joint in the body.
Another Factor: Beta-Adrenergic Desensitization
Another reason you can lose strength while dieting is due to beta-adrenergic desensitization.
The beta-adrenergic receptors are the ones that interact with adrenaline. At the muscle level, when activated by adrenaline, beta–receptors increase muscle contraction strength and speed. At the brain and nervous system level, they’ll increase coordination, drive, willpower, and confidence.
So, when your beta-adrenergic receptors respond well to adrenaline, your chance of optimal physical performance is much higher.
But if they’re not responding well to adrenaline (when they’re desensitized or downregulated), strength and speed go down. You also find yourself in a worse mental state.
Why’s that relevant to dieting? You desensitize the beta-adrenergic receptors by overproducing adrenaline – either bursts that are excessive or adrenaline levels that stay high for too long.
Adrenaline is increased in large part by cortisol. Cortisol increases the conversion of noradrenaline to adrenaline.
One of the functions of cortisol is to mobilize stored energy. When you’re dieting, you need to mobilize more energy, so cortisol production goes up and so does adrenaline. That’s why a lot of people have a hard time sleeping when dieting.
Dieting can lead to a decrease in physical and mental performance by making you less responsive to adrenaline. When that happens, strength goes down more across the board. But it normally takes longer to occur than the strength loss from lowered passive stability.
Another reason for a loss of strength is your mental state. If you feel small and don’t sleep well, it’ll be much harder to get amped up to lift big weights. It’s like you program yourself to believe that you’re losing muscle and getting weaker – it’s a self full-filling prophecy.
And if your strength isn’t even going down? That’s a clear sign you’re not losing muscle.
What About the Scale and the Mirror?
You may expect to be at a certain weight when you get to the leanness level you want. This is common. But when you begin approaching that scale weight and don’t look lean yet, you assume it’s because you lost muscle along with the fat.
But, if you’re like most lifters, the reality is that you just had more fat to lose than you thought. You also carried less muscle than you assumed. Not fun to hear, but this is what happens to many people.
Here’s When Muscle Loss Does Occur
Sure, you can lose muscle when dieting. Here are four reasons why:
- It can happen when under 9-10 percent body fat. Even then, it’s not automatic, just more likely to occur.
- It can happen when you’ve been dieting for a very long time.
- It can happen if the level of caloric restriction is excessive. For example, losing more than three pounds a week after the first week.
- It can happen if your cortisol is chronically elevated or you have lowered mTOR and IGF-1 levels. These factors can make it harder to build muscle or retain it while in a deficit.
The former (cortisol levels) will occur when cutting calories. That’s just a fact. But cortisol can also be released due to life stress and the training session. A lot of people who actually lose muscle when dieting only do so because they’re afraid of losing muscle.
What?! Yes, when you’re afraid of losing muscle, you actually just might.
You may dramatically increase your training volume and “kill it” in the gym in the hopes of preventing muscle loss. When lifters feel flatter or more deflated because of their diets, they often do a stupid amount of volume to get that pumped feeling.
That excessive volume will lead to excess cortisol production, leading to muscle loss. It can also cause too much muscle damage for your body to recover from. Your capacity to repair and build muscle will be much lower if you cause too much muscle damage in that state… and then you CAN lose precious muscle tissue.
How To Prevent Muscle Loss
- Use an appropriate caloric intake. Aim for about a two-pound loss per week after the first week (in the first week, you’ll likely lose more), at least until you’re around a true 10-11 percent body fat. At that point, if you want to get leaner, you should shoot for around a one-pound loss per week.
- Keep protein (Buy at Amazon) high. Shoot for a little over one gram per pound of your starting body weight. Don’t lower that amount as your body weight goes down.
- Keep carbs around your workout. This will help decrease the cortisol response, maintain glycogen stores, and improve performance. I’d also consume sodium around the workout. Surge Workout Fuel (Buy at Amazon) is perfect for this because of the type of carbs and electrolyte content, which kills two birds with one stone.
- Keep sodium high. It’ll help keep you fuller-looking and get pumps.
- Don’t be stupid with training volume. It won’t be as helpful as intensity. Do fewer sets but push them to the limit or close to it.
- Have the right expectations. It’s all about mindset. You’ll feel flat and feel smaller in your clothes. You might not look any better for a good number of weeks because you look smaller but aren’t yet lean enough to look defined. Mentally, this period is hard. Know that you’re not losing muscle, and if you endure, you’ll look better.
A Final Reality Check
There’s one thing I want to mention, and it may change your decision on whether or not to proceed. Depending on how lean you are at the moment, you might need to get much smaller than you think to get truly ripped.
Let’s say you lose 10 pounds and you still don’t look all that lean. Your first reaction will be to think that you’re losing muscle instead of fat. But, in reality, you just needed to lose more fat than you expected.
Here’s a real-life example. A guy approached me for coaching. He wanted to do a bodybuilding show. He was 5’9" and 220 pounds. He told me he thought he could be at the bottom of the heavyweight or top of the light-heavy class – so 198 to 204-pound class. I told him that on contest day, he’d be 176.
He looked like he saw a ghost. The guy wasn’t fat, mind you. Just the typical bro physique. Muscular, but not defined.
Fast forward to contest day. He ended up being EXACTLY 176 pounds! He won his class and the overall.
Bottom line is, he needed to lose about 44 pounds to look as ripped as he wanted, even though he initially believed he needed to drop 22 pounds.
So if you’re worried about catabolism, it’s possible you just had an erroneous perception of how much muscle you carried and how much fat you have to lose.
