How to Build Muscle and Lose Fat

Most of us would like to build muscle and lose fat simultaneously, but is it possible? Should you focus on one thing at a time?

Many people believe that accomplishing both things at the same time is close to impossible or that only absolute beginners can do it.

In this article, you’ll learn why that is not necessarily the case and how to make this challenging but possible task come true and reach your fitness goals without bulking up.

Body Recomposition: Build Muscle and Lose Fat at the Same Time

The process of simultaneous fat loss and muscle gain is called body recomposition: you change your ratio of lean body mass to fat mass, and you do it without bulking and cutting phases. 

Bulking means maximizing muscle growth by increasing your calorie intake and gaining weight. A caloric surplus inevitably means putting on body fat as well as muscle, even with high-intensity weight training and aerobic exercise.

Cutting is when you create a calorie deficit by eating less than your burn each day and maybe adding cardiovascular exercise to your strength training program. You reduce the body fat you put on during your bulking phase to reveal the muscle you gained.

That’s the traditional way of building muscle and losing fat: one thing at a time.

Body recomposition is when you do both things simultaneously. Losing body fat while gaining muscle is a holy grail among bodybuilders and fitness enthusiasts.

Build Muscle and Lose Fat Simultaneously: Is It Possible?

Many people believe that you can’t burn fat and build muscle simultaneously, but the good news is that they are wrong. It’s more challenging, yes, but not impossible.

Plenty of scientific research shows that it is quite possible to accomplish both things at the same time, even over a more extended period.

Beginners and Untrained

When you have just started training, your capacity to build muscle is at its peak, even if you don’t have the greatest of genetics. Newbie gains are real. If you also have more body fat than you need, body recomposition shouldn’t be an issue.

  • Overweight subjects lost several kilograms of fat and gained a lot of muscle in a 14-week study while engaging in both strength and endurance training.

It’s not just possible for a beginner, regardless of age, to lose body fat while gaining lean mass, but quite doable. All it takes is some heavy weights and enough protein.

What About Experienced Lifters?

Body recomposition as a beginner is one thing, but what if you’re a reasonably experienced lifter or bodybuilder? You might not be overweight, but you carry some excess body fat. You want to get in shape without sacrificing your ability to continue gaining muscle mass.

The answer is yes here as well. However, it won’t be quite as easy. You won’t see any dramatic increases in muscle mass in a few months while losing a lot of body fat. But you can still gain some muscle while losing fat. The scientific literature offers support for your endeavors as well.

  • Italian elite gymnasts eating less than 2,000 calories a day lost weight, reaching body fat levels close to 5% after a month of regular training.

As you can see, even trained individuals can lose body fat while gaining muscle mass. However, the possibility of something does not necessarily guarantee that it will happen, which is apparent in a case study of a natural bodybuilder during competition prep. He lost almost as much muscle mass as body fat during a 14-week contest diet, even though he trained adequately and followed a strict diet plan.1

Fat-free and fat mass in a natural bodybuilder dieting for 14 weeks, going from 14% body fat to 7%.

Building Muscle and Burning Fat Is Not Just About Calories

Muscle protein synthesis and muscle protein breakdown co-occur 24/7, from before birth until the day you die.

Muscle protein synthesis minus muscle protein breakdown equals muscle protein balance or just protein balance for short.

  • When your muscle protein synthesis exceeds your muscle protein breakdown, you are in a positive protein balance. Your muscle mass increases.
  • When breakdown exceeds synthesis, you enter a state of negative protein balance, leading to a loss of muscle mass.

How many calories you eat is vital for your basal muscle protein synthesis. During a calorie deficit, you build less muscle. Maintaining or increasing your muscle mass keeps your basal metabolic rate stoked and makes it easier to stay at low levels of body fat year-round.

The most powerful way to stimulate muscle protein synthesis is by hitting the weights. Strength training increases muscle protein synthesis significantly for up to 24 hours.2 3 4 That increase is not dependent on calories. Instead, all that’s required to build muscle after a workout is amino acids, the building blocks for your muscle cells you get from eating protein.

You don’t need a massive meal to boost muscle protein synthesis following a strength training session. Protein, like a whey protein shake, is sufficient to flip the switch and start building muscle.

Creating a positive protein balance this way increases your lean mass following a workout, even though you don’t eat enough for calorie balance. That’s how powerful the anabolic effect of strength training is when you combine your training session with a protein intake.

build muslce and lose fat

As with muscle protein, you both store and burn body fat simultaneously.

  • When you are in a calorie balance, you accumulate as much fat as you burn. That means that your body fat does not increase or decrease.
  • If you increase your food intake to a calorie surplus and eat more than you burn off, you gain weight and body fat.
  • If you burn more calories than you consume, your body weight goes down, as do your body fat levels.

The trick to building muscle and losing fat is to stimulate muscle protein synthesis regularly while eating plenty of muscle-building protein and fewer calories you take in.

Sounds easy?

It is, in theory. The challenge is to stay consistent over time.

What Time Period Are We Talking About?

Every day, your muscle protein balance and body fat balance shift from positive to negative and back repeatedly. Regardless of your calorie balance over the day, you lose and gain muscle all the time. 

After a meal, you build muscle and store more fat than you burn.

Between meals, as you enter a fasted state, you break down more muscle tissue and fat mass than you build or store until your next meal. 

Over a month or longer, the synthesis and breakdown of muscle and fat are about equal if you eat as much as you need and without strength training. In other words, you are weight stable, and so is your body composition.

When trying to build muscle and lose fat simultaneously, the time period we’re talking about is an important factor.

The longer the time, the easier it gets to do both things “at the same time.” If we are talking months, it shouldn’t be all that hard at all. In that case, you will have alternated between gaining muscle mass and losing body fat many times.

If you have been training correctly and eaten enough protein during this time, you should have improved your body composition. That means that you have built muscle and lost fat at the same time over those months of training and dieting. However, you probably haven’t done so at the same time if we are talking about the exact second, the same minute, or the same hour.

If the measurement period is short, it can be impossible to do both things simultaneously. The hours after a Thanksgiving dinner, for example, you will build more muscle than you break down. However, you will surely gain body fat at the same time. Over Thanksgiving week as a whole, however, you can lose weight and body fat despite that day of overfeeding, as long as you restrain yourself during the other days.

How To Build Muscle and Lose Fat

To gain muscle mass, you need to be in an anabolic state. To lose weight and body fat, you need to take in fewer calories than you burn. Losing fat is a catabolic process. You need to be in a calorie deficit. You can’t, unfortunately, get away from that fact.

So, if you want to gain muscle while losing body fat, you must prime your muscle protein synthesis. It must exceed your muscle protein breakdown over time while you remain in a calorie deficit.

That’s not a simple task. Anabolism and catabolism are opposites of each other. Body recomposition requires effort and discipline. If you eat and train haphazardly, your results will also be haphazard.

The three-step solution for anyone looking to build muscle and lose fat at the same time is as follows:

  • Engage in resistance training regularly. You keep your muscle protein synthesis elevated and build muscle mass even though you’re in a caloric deficit.
  • Eating a high-protein diet plays an important role. Getting plenty of protein ensures your muscles have the building blocks they need to grow and prevents muscle breakdown.
  • Cut calories. Reducing your caloric intake and eating fewer calories than you burn is essential for weight and fat loss.

Training to Build Muscle and Lose Fat

The best way to train to build muscle and lose fat simultaneously is the same way you’d train for muscle building at any other time. However, an important thing to consider is your decreased ability to recover during a calorie deficit. There is no standard protocol for body recomposition training, but the following guidelines make for an approach that fits most lifters:

  • Perform 10–20 total sets per muscle group per week. That’s the optimal training volume to maximize muscle hypertrophy according to up-to-date research.

Read more:

>> How to Build Muscle: Exercises, Programs & Diet

You can, of course, follow any training program you like. But if you prefer a pre-programmed and highly effective workout split for building muscle, we offer an expensive selection for different experience levels in our StrengthLog workout tracker:

  • Beginner Barbell Program: Our most time-effective training program for the beginner to get started. Three workouts per week with three exercises per workout provide a solid foundation of training for your whole body. This program suits those new to strength training who want to start an effective routine that doesn’t take too much time since it is wholly based on compound movements.
  • StrengthLog’s Full Body Hypertrophy: In this program, things get a little more serious. You still train three times per week, but you train all muscles more thoroughly each workout, using a combination of compound and isolation movements. This is an excellent three day-routine for building muscle!
  • StrengthLog’s Upper/Lower Program, 4 days/week: The number of workouts has increased to four per week in this program, with the training split between two upper body workouts and two lower body workouts. This program is more minimalistic than the one above and only contains compound movements. But if you want to, you can complement it with additional isolation exercises.
  • Bodybuilding BalletOur most popular training program for bodybuilding, designed as a classic “bro-split.” It’s a premium program for intermediate and advanced bodybuilders, available in four- five- or six-day training versions.
  • Bodybuilding Blitz: a 5-day workout split that combines training for muscle growth and strength. The training sessions are short, which can be beneficial if you’re on a tight schedule, but highly effective nonetheless.

Read more:

>> The 10 Best Bodybuilding Splits: a Complete Guide

These programs, and many more, are available exclusively in our workout app StrengthLog.

Some programs, like Bodybuilding Blitz and Bodybuilding Ballet, require a premium subscription, but StrengthLog itself is entirely free. You can download it and use it as a workout tracker and general strength training app – and all basic functionality is free forever.

Want to give premium a shot? We offer all new users a free 14-day trial of premium, which you can activate in the app.

Download StrengthLog for free with the buttons below:

Download StrengthLog Workout Log on App Store Bodybuilding Blitz
Download StrengthLog Workout Log on Google Play Store Bodybuilding Blitz

>> Click here for our list of training programs.

Eating to Build Muscle and Lose Fat: The Importance of Protein

Your training is not the only thing that determines whether your attempts to recomp your body end up being successful or unsuccessful. As mentioned earlier, your protein intake is an essential factor. Two well-controlled studies demonstrate this quite effectively.

  • In the first study, 40 young men reduced their calorie intake by 40% for a month. They combined strength training and high-intensity interval training six days a week. Half the subjects ate 1.2 grams of protein per kilogram of body weight and day, while the rest ate double that amount. That means that all participants exceeded general recommendations for protein intake. The high-protein group increased their muscle mass significantly. The group that ate 1.2 grams of protein per kilogram of body weight per day did not lose any muscle. However, they didn’t gain any, either. In addition, the high-protein group lost more weight and body fat.
build muscle and lose fat

“Calories in minus calories out” is the number one factor for weight loss. However, that equation does not tell how your body uses those calories. By engaging in strength training and keeping your protein intake high, you use more of what you eat to build muscle.

Read more:

>> Protein Intake: How Much Protein Should You Eat per Day?

>> Eating for Muscle Growth: When, How, and How Much to Eat for Adding Lean Mass

Keep Your Expectations in Check

You can lose body fat fast. The larger your calorie deficit, the quicker you lose weight and body fat. Gaining muscle mass is much more challenging and takes a much longer time. When you’re new to strength training, your results come pretty rapidly, but not at the same rate as your ability to lose fat. If you are already well-trained, gaining a few hundred grams of muscle a month is excellent. On the other hand, you can quickly lose several kilograms of body fat during the same month.

Adjust your expectations according to this. Don’t expect to be able to replace a lost kilogram of body fat with a kilogram of muscle mass. That is not realistic.

If you are not overweight, you have to accept that you can’t gain muscle mass at the same rate you can lose fat. The gymnasts in the study we mentioned earlier gained muscle while reaching body fat levels similar to those of a stage-ready bodybuilder. However, the average person should probably not expect to pack on pounds of muscle like that on a strict diet. The leaner you get, the harder it is to gain muscle while losing fat. In the last month of a pre-contest diet, most bodybuilders don’t increase their lean muscle mass. Instead, they focus on losing as little muscle as possible. Your energy availability and hormonal status do not promote anabolism under conditions like that.

How to Build Muscle and Lose Fat at the Same Time

Let’s get down to the practical stuff! These are the key things to keep in mind when you’re trying to build muscle and lose fat at the same time.

  • Eat plenty of protein. At calorie balance or in a surplus, 1.6 grams of protein per kilogram of body weight (around 0.8 grams per pound of body weight) and day is enough to promote maximal gains in muscle mass for almost everyone. If you increase that to 2.2 grams per kilogram (or 1 gram of protein per pound) of body weight per day, you cover all your bases for sure, even if you are an elite strength athlete or competitive bodybuilder.

Carb Cycling

What about carb cycling? Carb cycling is a popular method intended to increase your ability to gain muscle while losing body fat simply by adjusting your carbohydrate intake depending on your activities. On training days, you eat more carbs to perform your best and increase your insulin levels. On rest days, you decrease your carb intake, create a more significant calorie deficit, and lower your insulin levels, thus burning more fat.

In theory, that is. Very few studies, if any, support this method to circumvent the “calorie in minus calorie out”-equation. Carbohydrates do not promote any extra muscle protein synthesis compared to protein alone. Fasting insulin levels are enough to max out your protein synthesis response to a protein-rich meal. How you distribute your carbohydrates and fat at a specific energy intake seems to have a minimal effect on your body weight and composition.

If you want to experiment with carb cycling, feel free to do so. It is most likely not detrimental in any way. I can attest to getting a better pump and performing better in the gym by carb-loading on training days and compensating with a lower carb intake on rest days during a diet. However, there is no scientific evidence that this leads to more significant fat loss or greater gains in muscle mass.

Intermittent Fasting

Regular low-calorie diets and intermittent fasting are equally effective for losing weight and burning fat.5 6 7 8 Intermittent fasting might help you maintain muscle mass during a fat-loss diet, although we don’t have enough research to say for sure.

If you enjoy the intermittent fasting lifestyle, go for it. It probably won’t offer any significant benefits in your efforts to build muscle and lose fat, but it won’t prevent you either. As long as you stick with the number of calories suitable for your body, a balanced diet, and keep your protein intake high, you’re good to go with either option.

Read more:

>> Intermittent Fasting and Strength Training: The Ultimate Guide

Supplements to Build Muscle and Lose Fat

No supplements will do the job for you, but some are helpful for building muscle while losing fat.


Creatine is the single most effective supplement for gaining lean body mass and strength and improving exercise performance. While it has no proven fat-burning properties, research shows that people using creatine generally lose a little more body fat compared to placebo.

Protein Supplements

Reasonably inexpensive and convenient, a quality protein powder makes it easier to get enough protein. Whey protein concentrate or isolate are likely the best options if you use dairy products, while soy protein isolate is a high-quality plant-based alternative.


Caffeine stands at the ready whenever you need a pick-me-up or an energy boost, whether you prefer regular coffee or caffeine in supplement form. It is the active ingredient in most pre-workout products and has proven to be effective for improving performance in almost any type of exercise.

Read more:

>> The 5 Best Supplements to Gain Muscle

>> The 5 Best Supplements to Get Shredded

Want to learn more about dietary supplements? Which ones are worth your money, and which are questionable or useless? Check our StrengthLog’s Supplement Guide, our free guide where I review 26 of the most popular supplements.

Do You Build More Muscle if You Bulk First, Diet Later?

Maybe. An energy surplus makes it much easier to gain muscle mass. If you keep your overfeeding under control, you don’t have to acquire excessive amounts of fat along with the muscle.

It is pretty easy to maintain the muscle you have gained during a bulk when you switch to dieting your fat away. Maintaining muscle mass during a cutting diet is much easier than gaining muscle.

It is probably more effective in the long run to alternate periods of moderate overeating with periods of dieting. It might also be better for your mental well-being. Maintaining a calorie deficit over more extended periods can be challenging not just for your body but for your brain as well.

However, when you bulk and cut the traditional way, you invariably gain body fat during parts of the year. If you are not comfortable with that, staying in a calorie balance most of the year and peaking once or twice a year might be an alternative.

In addition, even if you give building muscle and burning fat at the same time a go, you don’t necessarily have to do it year-round. If nothing else, now you know that you don’t have to give up gaining muscle during a cutting phase.

Summary and Conclusion

Can you build muscle and lose fat at the same time?

Simple answer: yes.

More complex answer: maybe. You can’t say for sure that a particular individual will be able to. It depends on many physiological and behavioral factors.

Most of us wish we were born with better genetics for building muscle. Unfortunately, not everyone is genetically blessed. If you have to fight for every gram of muscle mass you put on, you will find it hard to build muscle and lose fat simultaneously, compared to someone whose biceps grow just by looking at the barbell. The same thing goes for your diet. Not everyone utilizes the food they eat in the same way. Some people build more muscle, while others store more fat at the same calorie intake.

Other factors, like your hormones, how well you sleep, and your entire life outside the gym, including stress, also affect your chances of gaining muscle while losing fat.

If you succeed in building muscle and fat at the same time depends on many things—some work for you, others against you.

It’s impossible to say if you can do it before you try. Physiologically, it is quite possible. And with the will to accomplish it, you probably can, with hard work and discipline. Give it a go!

Further reading:


  1. J Int Soc Sports Nutr. 2015; 12: 20. A nutrition and conditioning intervention for natural bodybuilding contest preparation: case study.
  2. Physiol Rep. 2018 Jul; 6(14): e13799. Resistance exercise stimulates mixed muscle protein synthesis in lean and obese young adults.
  3. The Journal of Nutrition, Volume 141, Issue 4, April 2011, Pages 568–573. Enhanced Amino Acid Sensitivity of Myofibrillar Protein Synthesis Persists for up to 24 h after Resistance Exercise in Young Men.
  4. Can J Appl Physiol. 1995 Dec;20(4):480-6. The time course for elevated muscle protein synthesis following heavy resistance exercise.
  5. J Transl Med. 2018; 16: 371. Intermittent versus continuous energy restriction on weight loss and cardiometabolic outcomes: a systematic review and meta-analysis of randomized controlled trials.
  6. Nutrients. 2019 Oct; 11(10): 2442. Effectiveness of Intermittent Fasting and Time-Restricted Feeding Compared to Continuous Energy Restriction for Weight Loss.
  7. Obesity Reviews, Volume 12, Issue 7, July 2011. Intermittent versus daily calorie restriction: which diet regimen is more effective for weight loss?
  8. N Engl J Med 2022; 386:1495-1504. Calorie Restriction with or without Time-Restricted Eating in Weight Loss.
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Andreas Abelsson

Andreas is a certified nutrition coach with over three decades of training experience. He has followed and reported on the research fields of exercise, nutrition, and health for almost as long and is a specialist in metabolic health and nutrition coaching for athletes. Read more about Andreas and StrengthLog by clicking here.