All the best advice on how to lose fat without losing muscle is stuff that you probably know already.
It’s not particularly exciting or new. And it’s not going to transform your body overnight.
But people are too quick to dismiss things that they think they already know.
“If it was that simple, everyone would be doing it,” they think to themselves. “Tell me something new.”
If you’ve made the mistake of drifting away from the basics in search of the next “new and revolutionary” approach to fat loss, I’ve put together a simple guide that explains exactly how to burn fat without losing muscle.
A nutrition and exercise program based on these principles will work for most people. Chances are it will work for you too.
But first things first. What does the term “losing muscle” actually mean?
When they talk about losing muscle, most people are referring to the loss of muscle protein. But there’s a lot more than just protein inside your muscles.
Take a close look at a slice of muscle tissue under a microscope. You’ll see stored carbohydrate in the form of glycogen, fat stored both in and between muscle fibers, as well as water.
When you go on a diet, the amount of glycogen, water and fat stored in your muscles is going to drop. In the first week or so of dieting, you’ll lose muscle glycogen and water a lot more quickly than you drop fat.
Given the fact that some of the material stored in your muscles has been lost, we could say that you’ve lost muscle, particularly as they take on a slightly “deflated” appearance.
All that’s happened is that your muscles have flattened out a bit because there’s not as much “stuff” in there as there was before.
Remember, you haven’t lost actual muscle protein. Rather, you’ve just lost some of the substances stored around those proteins, which can be replaced very quickly.
When I talk about losing muscle, I’m referring to the ongoing loss of muscle protein over a period of weeks and months, rather than the initial loss of glycogen, water or intramuscular fat.
1. The first “rule” when it comes to losing fat without losing muscle is to make sure your calorie deficit is set at the right level.
To lose weight, you need to create a calorie deficit. No matter what type of diet you’re following, be it Intermittent Fasting, the Paleo Diet or whatever else is popular this month, a calorie deficit is a required condition for weight loss.
So what exactly is a calorie deficit?
You’re said to be in a “calorie deficit” when there is less energy coming from the food you eat than your body needs to move, pump blood around your body and all the other stuff involved in keeping you alive.
What this means is that there’s a mismatch between the amount of fuel your body needs and the amount it gets from food. So it starts looking for an alternative.
In an ideal world, that alternative source of fuel would be the fat you have stored in your body. But your body will pull stored energy from any place it likes, including the muscle tissue that you’ve grown particularly fond of over the years.
If your deficit is too large, you can and will end up losing muscle as well as fat. Too small, and your rate of fat loss will be a lot slower than it otherwise would be.
When you lose muscle, you will end up losing weight more quickly.
That’s because one pound of muscle contains around 600 calories, compared to 3500 calories in one pound of fat.
For example, let’s say that you create a daily calorie deficit of 500 calories. In other words, every day you burn 500 calories more than you get from your diet. That comes to 3,500 calories per week (500 x 7 = 3,500).
If all of those calories came from fat, you’d lose just one pound in weight. But if all of those calories came from muscle (which is an unlikely scenario, but I’ll use it just to illustrate the point), you’d lose almost six pounds in weight.
To put it another way, 100% fat loss is the equivalent of one pound of weight lost, while 100% muscle loss is the equivalent of six pounds of weight lost.
Something you’ll need to consider when setting the size of your deficit is something called the P-ratio, which defines the fraction of an energy imbalance accounted for by changes of the body’s protein reserves .
“The P-ratio represents the amount of protein that is either gained (or lost) during over (or under) feeding,” explains Lyle McDonald. “It’s more or less the same for a given individual; they will gain about same amount of muscle when they overfeed as they lose when they diet.”
While there are many factors that influence the P-ratio, the two main ones are a) your initial body composition and b) the direction and magnitude of weight change.
What does all of this actually mean?
The more fat you have to lose, the greater the calorie deficit you can sustain without worrying about muscle loss.
If we took two people, one with high levels of body fat, and one with low levels of body fat, and fed them the same low-calorie diet, a greater proportion of the total weight lost in the leaner individual would come from muscle .
Which is basically another way of saying that the fatter you are, the more severe your diet can be.
2. The next step is to make sure you’re getting enough protein in your diet.
Why is protein so important? Firstly, protein does a better job at filling you up than carbohydrate or fat. Eat a protein-rich breakfast, for example, and chances are that you won’t eat as much food for lunch.
The figure below is from a University of Washington study where dieters were told to eat roughly twice as much protein as normal . The circles at the top represent daily calorie intake, while the diamonds at the bottom represent body weight.
As you can see, eating more protein led to a spontaneous reduction in calorie intake that lasted for the length of the study. In fact, calorie intake dropped by an average of 441 calories per day.
Protein also has a “muscle sparing” effect. If you don’t get enough protein while you’re on a diet, you’ll end up dropping muscle as well as fat.
3. Do some form of resistance training 2-3 times per week.
If you want to lose fat without losing muscle, it’s a good idea to do some form of strength training.
In one eight-week study comparing diet plus strength training, diet plus cardio, or diet only, all three groups lost roughly the same amount of fat . But the cardio and diet-only groups lost twice as much muscle as the strength-training group.
A similar study looked at the effect of diet plus strength training or diet plus cardio in a group of 20 obese men and women . Although the cardio group lost more weight, the strength-training group lost more fat (32 pounds vs. 28 pounds) and significantly less muscle.
How much weight you lose is a lot less important than where that lost weight comes from. If you drop 10 pounds of fat while gaining 3 pounds of muscle, your weight on the scales will only have dropped by 7 pounds. But you’ll look 13 pounds different.
I know that lifting weights twice a week might not sound like enough. But there’s actually plenty of research out there to show that it is.
So even if you only have the time (or motivation) to go to the gym twice a week, it’s still possible to lose the love handles, flatten your stomach and improve your muscle definition, just as long as those two workouts are set up correctly.
Remember, your main goal while you drop fat is to keep the muscle that you have right now. And studies show that you can maintain any given component of fitness, be it muscular size, strength or aerobic power, with a lot less work than it took to develop it.
The type of training that helps maintain muscle mass will be much the same as the training you did to build that muscle in the first place.
You’ll still be doing squats, deadlifts, rows, chin-ups (or pulldowns) and presses (bench press and overhead press), using a weight that limits you to somewhere between 5 and 15 repetitions per set.
However, much the same doesn’t mean exactly the same, and strength training in a calorie deficit is a slightly different story to strength training in a calorie surplus.
I can’t tell you exactly how to change your workout because I don’t know what you’re doing in the first place.
The one thing that should stay the same is training intensity. And by intensity, I’m talking about the amount of weight that’s on the bar when you lift it.
As an example, if you currently squat 300 pounds for five reps, then make sure to keep the weight at or around that level during the fat loss phase of your training.
That doesn’t mean you should stop trying to gain size and strength. But it’s not something you should necessarily expect, especially once you’ve moved past the beginner stages of training.
Someone who is very overweight and new to lifting weights will find it relatively easy to gain strength while dropping fat. As you get leaner, your strength gains will slow down. So you’ll need to modify your expectations accordingly.
Eventually you’ll reach the point where the best you can hope for is just to maintain your strength. It’s not unusual for competitive bodybuilders to get significantly weaker in the weeks before a contest.
There is not a perfectly linear relationship between the size of your muscles and the amount of weight you can lift.
A 50% increase in strength, for example, won’t translate into a 50% increase in size. That’s because there are other factors (most notably your nervous system doing a better job of using the available fibers in a given muscle) that contribute to making you stronger.
But for our purposes, the link between strength and size is close enough. If you’re losing fat while maintaining (or even gaining) strength, you’re on the right path.
4. Use cardio, particularly very intense cardio, in moderation.
With the current trend for high-intensity interval training (HIIT) and whole body workouts, there are plenty of people out there running into problems with fatigue.
Anyone trying to combine heavy strength training 2 or 3 times a week with 3-4 interval workouts AND a calorie-restricted diet is going to end up getting burned out very quickly.
If you’re just starting out, you can forget about cardio altogether and rely on diet and strength training to create the calorie deficit that you need to lose weight.
When your rate of fat loss starts to slow down, add some low-intensity steady-state (LISS) cardio to your program.
My personal favorite is 30-60 minutes of walking first thing in the morning. Not only does it burn extra calories, a brisk morning walk in the fresh air is a great way to clear your mind and set you up for the day.
The benefit of LISS is that it burns additional calories while having only a minor impact on your muscle-building efforts in the gym.
You can’t train “all out” on a daily basis, mainly because your body will need time to recover. But low-intensity activity, such as walking or cycling, can be done every day. And because you can do it more frequently, this type of exercise can end up making a significant contribution to fat loss.
There are supplements you can take and a few other dietary tweaks that will speed up your progress a little. But the steps above are going to be responsible for the vast majority of your results.
One last point: If you have lost some muscle, don’t panic. You can get it back again quite easily. It’s not like it’s been lost forever.
In fact, re-building lost muscle usually happens a lot more quickly than gaining it in the first place.
That’s because the number of nuclei (which play a crucial role in building new muscle) in muscle cells increases when you lift weights, even before the muscle cell itself starts to grow.
But those nuclei aren’t lost when your muscles shrink. Instead, the extra nuclei remain in place, forming a type of “muscle memory” that allows lost muscle mass to grow back more quickly.
If you enjoyed this post, there’s a good chance you’ll also like Truth and Lies about Burning Fat: 10 Weight Loss Myths Debunked By Science.
It's a FREE 16-page special report (PDF) I put together to debunk 10 popular weight loss myths that are still widely believed, despite all the evidence to the contrary. You can download a copy here.
About Christian FinnChristian Finn holds a master's degree with distinction in exercise science, is a certified personal trainer and has been featured on BBC TV and radio, as well as in Men's Health, Men's Fitness, Fit Pro, Zest, and Perfect Body magazine.
1. Hall KD. (2007). Body fat and fat-free mass inter-relationships: Forbes’s theory revisited. British Journal of Nutrition, 97, 1059-1063
2. Bryner, R.W., Ullrich, I.H., Sauers, J., Donley, D., Hornsby, G., Kolar, M., & Yeater, R. (1999). Effects of resistance vs. aerobic training combined with an 800 calorie liquid diet on lean body mass and resting metabolic rate. Journal of the American College of Nutrition, 18, 115-121
3. Geliebter, A., Maher, M.M., Gerace, L., Gutin, B., Heymsfield, S.B., & Hashim, S.A. (1997). Effects of strength or aerobic training on body composition, resting metabolic rate, and peak oxygen consumption in obese dieting subjects. American Journal of Clinical Nutrition, 66, 557-563
4. Hall KD. (2008). What is the required energy deficit per unit weight loss? International Journal of Obesity, 32, 573-576
5. Weigle DS, Breen PA, Matthys CC, Callahan HS, Meeuws KE, Burden VR, Purnell JQ. (2005). A high-protein diet induces sustained reductions in appetite, ad libitum caloric intake, and body weight despite compensatory changes in diurnal plasma leptin and ghrelin concentrations. American Journal of Clinical Nutrition, 82, 41-48
6. Helms ER, Zinn C, Rowlands DS, Brown SR. (2013). A systematic review of dietary protein during caloric restriction in resistance trained lean athletes: A case for higher intakes. International Journal of Sport Nutrition and Exercise Metabolism