Can You Build Muscle in a Calorie Deficit?
We all want to slim down our fat and bulk up on our muscles. Whether it’s for aesthetic reasons, personal goals, health—it doesn’t matter, we all need a safe and effective way to get there.
Some of us face the issue where we want to lose weight while also building muscle simultaneously, and until recently, that seemed like an impossible feat. For those who just wanted to trim half a percent of their total body fat here and there, this also applies.
Caloric deficits are key to weight loss, but they can actually be used to help you bulk up as well. We’re going to cover everything about it so you can trim and bulk at the same time.
What is Caloric Deficit?
You need a certain amount of calories to maintain your current weight each and every day. This depends on your gender, age, height, and current weight.
A caloric deficit is when you intentionally take in less than the required amount of calories needed to sustain your current weight.
Weight is lost in the kitchen before it’s ever lost in the gym. While annual reports come out from varying sources that cite different percentages (e.g. 80% diet and 20% exercise), we can take one point away from all the headlines and Good Morning America segments—diet is more important to weight loss, but exercise is still critical.
However, you don’t want to go too hardcore with a caloric deficit. A caloric deficit shouldn’t exceed more than 40% of what you need to intake to maintain your current weight, otherwise, you’ll start siphoning nutrients from other parts of your body, and that’s when you get into dangerous territory.
You can actually siphon the calcium from your teeth and your bones if you aren’t careful—this is serious stuff.
Eat less than you need to maintain your current weight, and then work out (but account for the calories you need to work out).
Best Ways to Achieve Caloric Deficit
It sounds simple, it really does, but the best way to achieve caloric deficit is to simply track everything that you eat in a single day.
Once you see the numbers play out on a sheet of paper, even if you eat normally for that first day, you’ll realize how startlingly easy it is to exceed your recommended daily allowance (RDA) of calories.
You can also burn more calories than you consume, so if you consume 100 over your RDA, and you burn 250 calories, then hey—you’re losing calories! Not enough to lose considerable weight, but it’s better than gaining, right?
Plus, working out helps improve muscle health and heart health, so it’s a two-for-one win.
And that’s it—there’s no other way to achieve a caloric deficit, other than combining an intentional dietary deficit with exercise, which is what you should be doing.
Even so, you should still count what you eat (it’s actually even more important now) so that you know where you stand at the end of the day.
Science Behind Muscle Building
Let’s try to condense this as much as possible while still making sense. At its base, your body is a collection of proteins called amino acids. Muscles are made of protein, so you need to intake protein to build muscle.
Your body needs a certain amount of protein each day to maintain your muscles, so you need to consume more protein to have a surplus.
Protein can help stimulate the production of the human growth hormone, most notably testosterone. This helps you allocate protein and build muscles.
You will use B vitamins, proteins, and other various vitamins to build muscle and protect your joints. You will also burn through some as fuel. You need to consume a slight excess of these vitamins and minerals to give your body something to nurture muscles with.
In short, hormones like testosterone and insulin help with cell synthesis. This makes it easier for your body to process protein, promote tissue growth to support new muscles and larger muscle volume, stimulate protein synthesis hormones such as anabolic hormones, and activate satellite cells (a stem cell that helps muscles grow).
It starts with diet, but diet alone doesn’t build muscle. When you do resistance training (known as strength training), your muscles are forced to work against, well the weight of force itself.
Your muscles are getting used to the new climate under more pressure, and are trying to adapt to let you meet the needs that resistance and force is communicating that your body needs.
That force initiates muscle growth, which is made possible by your attention to nutrition and lack of excessive caloric consumption.
Do You Have to be in Caloric Surplus to Build Muscle?
Yes and no. If you have a low body fat content, then yes, you have to bulk up to build muscle. Your body needs some amount of fat, even if it’s a very low percentage.
It’s not going to burn through everything you have, so if your muscle growth stalls, you might need to bulk.
But you can gain muscle in a caloric deficit if you have body fat that you’re trying to get rid of. Your body can be trained to use that fat as a fuel source and burn through it while you sleep, which we’re going to explain later on in this guide.
How to Build Muscle While in Caloric Deficit
It’s short, sweet, and to the point: perform resistance training, build up your muscles, and feed your body with proper nutrition. Even if you are taking in less calories, the quality and nutritional profile of the food you’re eating matters a lot.
If you don’t have the body fat to burn or spare, then you can’t gain muscle mass while in a caloric deficit. Your body will adapt, but it won’t sacrifice the small amount of necessary fat it needs.
Best Foods for Caloric Deficit Gains
Just because you’re in a caloric deficit doesn’t mean you’re not gaining energy. Stick to this list to get maximum energy and nutrition without peaking over your RDA.
- Full Fat Yogurt: Greek yogurt is a good example of this. Stick to healthy dairy-based fats.
- Seeds and Nuts: High protein, a bit of salt for electrolytes, and various vitamins and minerals. Go for almonds, pumpkin seeds, sunflower seeds, and any other snacking seed you enjoy.
- Healthy Fat: You can get this from olive oil in your salad, or avocados on your toast (guacamole is a great source as well).
- Lean Fish: Nothing deep-fried. Stick to salmon, cod, and trout. Shellfish can have high mercury content, so only have those every now and again.
- Legumes: Beans have protein, but they also have a complex nutritional profile. Chickpeas, black beans, lentils, and other legumes are helpful as well.
- Whole Grains: Oats, barley, brown rice, and quinoa are all rich in protein (or at least contain a decent amount of it), help you feel full, and stave-off hunger so you can maintain that caloric deficit.
How to Train on Caloric Deficit for Muscle Gains
This can only be done if you have bodyweight that you want to get rid of, even if it’s not a triple-digit number. As long as you have fat that you want to shed, you can tell your body to burn it for energy.
When you’re sleeping, you’re not eating. I know that’s a very basic and silly statement, but bear with me for a moment. You wake up and literally break your fast, but if you know what intermittent fasting is, just apply that methodology to burning fat instead of calories.
As long as you perform strength/resistance exercises, your body continues to burn calories for a short while after (depending on the severity it can be up to 36 hours afterward, but there’s a lot of science in both directions).
While you sleep, your body is using up stored energy to repair muscles, tissue, and help your brain go through REM sleep. It’s not going to just stop necessary sleep-related functions because you didn’t have a snack before bed.
It’s going to use fat and turn it into body fuel while you sleep.
Focus on resistance training to continue burning fat while you sleep, and if you can make that into a full-body exercise, go for it. The more muscles you can safely engage during your resistance training days, the better.
Lifestyle Changes Needed
If you truly want to maintain a caloric deficit and gain muscle at the same time, you have to remember that your body has to burn existing fat, so you need to be on a weight loss goal, otherwise, you have to intake more calories to gain the necessary weight to build muscle.
But for this section, we’re going to talk about lifestyle changes to actually hit a caloric deficit in the first place so you can control your diet and fitness.
- Drink More Water: Water is essential to all functions in your body, such as metabolism of your muscles, heart health, circulatory function, joint lubrication, the list goes on and on. It’s imperative that you drink more water than you are right now. About a half-gallon per day for the average-sized man or woman is where you should aim.
- Avoid Added Sugar: Sugar leads to fat, and not the kind that’s healthy for you. Yes, we talked about turning fat into fuel for your body, but not having it in the first place is the best-case scenario. Added sugar is horrible, case and point. Avoid foods that have it.
- Wake Up at the Same Time Every Day: Your circadian rhythm directly affects how your body holds onto calories, and how you get rid of fat, how your body metabolizes, you get the picture. It only takes about two weeks of sleep to get your circadian rhythm set, but you have to make sure you go to bed (and fall asleep) at the same time every night, and wake up at the same time every morning. This is tough as nails to achieve, but then it becomes a habit.
- Daily Cardio: Some people really despise cardio, but it’s important. Some sources say you shouldn’t exceed 150 minutes of moderate-intensity cardio every week, and there’s merit to that. But light cardio for 20 minutes each day? That doesn’t even hit the weekly limit and it’s less intense. Going on a walk or hitting the treadmill on 30% power for 20 minutes every day helps you stay motivated to lose weight thanks to the way it changes brain chemicals. That, and you’ll be less likely to snack since you don’t want all that hard work to go to waste.
- Resistance Training 3 Days a Week: Strength training is a must. Not just for gaining muscle, but for losing weight through a caloric deficit. Resistance training has the ability to kick in the afterburn effect, which means you lose calories for hours after you leave the gym. That, and training your muscles helps you target where your body should be looking for fat to turn into fuel.
- No Drugs, Alcohol, or Tobacco: This is the unfun one that makes everybody hate me when I tell them, which is why it’s at the end. Everyone has vices, even if it’s just a six-pack on a Sunday afternoon after a full week of 50+ hours of grueling work. But if you’re serious about gaining muscle and losing weight at the same time, you need to avoid alcohol, avoid tobacco, and any recreational drugs. Beyond the calories in beer and liquor, they change your gut bacteria and affect your metabolism. Occasional wine will be okay, but that’s it.
Building Muscle the Smart Way
Your body can use fat as fuel, and once you know how to do this safely, you can successfully trim down your body fat content while increasing muscle mass.
This isn’t a permanent change in how you should live your life or your workout regimen, but it is a way to get there faster and then switch to a diet and exercise routine to maintain your new body.