Body Recomposition: How to Lose Fat and Build Muscle

by | Oct 29, 2023 | Nutrition

A higher proportion of muscle and less fat on the body not only looks good, but are associated with better health and allows athletes to maximize performance.

Optimal body composition depends on your goals and where you start.

Therefore, it makes a difference how an athlete with the goal of improving running performance or an obese person with the goal of losing weight will approach body recomposition.

How to approach body recomposition?

You will not have the toned look you are after if you just lose fat! You also need to build muscle. A skinny-fat person with less fat is still skinny person.

There are two ways to approach body recomposition:

  • Alternate between weight loss and muscle building cycles,
  • Lose weight and build muscle at the same time.

The method you choose depends on several factors:

  • Training status;
  • Your current body composition;
  • How much time you have to achieve your goals;
  • Which goal is more important to you – to build muscle or to reduce fat;
  • Which approach you prefer.

Current body composition

The leaner we are, the harder it is to reduce fat.

The leaner you are, the more FFM you will lose on a diet. The major cut-off point is at about 15% body fat

The leaner you are, the more Fat-Free Mass you will lose on a diet. The major cut-off point is at about 15% body fat for men.

How well-trained you are

The closer you are to your genetic potential, the harder it is to build muscle.

Eric Helms proposes to use the rate of improvement as the best metric to assess the level of the athlete.

Eric is a research fellow at the Sports Performance Research Institute New Zealand at Auckland University of Technology, pursuing research in training, nutrition and psychology for strength and physique sport.Eric has a PhD in Strength and Conditioning with a research focus on auto-regulating powerlifting, a masters with a research focus on protein and macronutrient manipulation for dieting bodybuilders, a second masters in exercise science and health promotion, and a bachelors in sports management, fitness and wellness. Also an athlete, Eric earned pro status as a natural bodybuilder with the PNBA in 2011, is a raw powerlifter in the IPF, and dabbles in weightlifting

How often you add weight, increase the number of repetitions, or your RPE (rate of perceived exertion) decreases? (This assumes you have a good training program, nutrition and sleep).

  • Beginner – every workout
  • Intermediate – every week or every other week
  • Advanced – can see some improvement during a 8-12 week training cycle
  • Elite – very little improvement over a year

How much time you have to achieve your goals?

Changing body composition is a long process that is not straightforward.

If you think of an athlete with an athletic physique and look at how they train and what they eat, you may get the impression that they are building muscle and burning fat at the same time. What we often don’t realize is that those who have been playing sports since they were young and eat well enough can appear to make progress without much effort. This is an example of how small changes show up over a long period of time. But there are many people who haven’t played sports all their lives or have had a long layoff and want to lose excess body fat and build muscle don’t want to wait 20 years for results.

Which goal is more important to you?

It’s essential to answer:

  • Can strength training and muscle building help to lose weight? Building muscle helps to lose weight through training and muscle also burns about 3x as much calories as body fat. Strength training during a diet reduces muscle loss.
  • Can the energy deficit required for weight loss make building new muscle impossible? Strength training in an energy deficit reduces the body’s ability to build muscle mass. However, it does not prevent strength gains.

Build muscle and burn fat at the same time

Building muscle and burning fat at the same time is commonly referred to as body recomposition. Body recomposition is appealing because many are put off by the idea of gaining weight when their ultimate goal is to lose weight and reduce fat.

Who can build muscle and burn fat at the same time?

  • You have a lot of body fat
  • you have a low volume of muscle mass
  • you are returning to training after a long time
  • you’re a newbie
  • your previous training plan, sleep, nutrition or all of the above have been inadequate

Practical obstacles

To build muscle and burn fat at the same time you need to be anywhere from a moderate caloric surplus (+250kcal/day) to a moderate deficit ( <500kcal/day).

The problem is that people don’t know their maintenance calories and have vastly different energy requirements from day to day. Therefore, trying to keep within a small range is difficult to achieve, especially if you can’t precisely track all the food you eat.

Changes in the physique during body recomposition are difficult to monitor. If we are trying to lose weight and build muscle at the same time, the changes in physique are not as visible. Aside from beginners, the changes take months, which can be demotivating.

Mindset problems

With body recomposition, body weight sometimes  drops, sometimes stays the same, and sometimes even increases. Many people who want to lose weight get scared if their weight is not decreasing, or even increases. If your goals is to lose fat and build muscle, you can’t be too attached to the number on the scale.

Alternating muscle building and weight loss at different time periods.

Alternating muscle building and weight loss is especially suitable if:

  • you have little body fat,
  • you have been training consistently for several years,
  • you don’t have major gaps in your training program, sleep or nutrition
  • you have a limited period of time (less than a year)

Building muscle mass is a slow process even if we have an ideal training program, enough energy and protein, and rest. For men it can be 0.25-0.5kg/week, for women only half of that.

If you want to put on 3kg of muscle mass and have no time limit. It can be done with minimal fat gain in a year or two. If you want to do it in 3-6 months, you have to increase both stimulus (exercise) and energy intake, which also means more fat gain (maybe 1.5-2kg).

For advanced lifters, slower, more conservative approaches to weight gain are recommended to minimize body fat gain while maximizing muscle growth. A small surplus of 100-300 calories is suggested.

In a shorter time period, one year, it is more effective to focus separately on gaining muscle mass and losing weight.

How long should a bulk and cut cycle be?

A minimum of 6 months is recommended, but ideally a year or two. Because weight loss is much faster than building muscle, it is advisable to focus on building muscle mass or being in a caloric maintenance most of the time.


time of the year spent cutting

How to add muscle with minimum fat gain?

There is a difference in how much energy your body can use to build muscle. According to studies beginners’ bodies can create up to 3kg of muscle a month with almost no fat gains, while advanced athletes might benefit from a more modest approach.

First, assess your training level (described above).

Eric Helms recommends using body weight to measure progress.

Beginners – aim to increase your body mass by up to 2% / month

Intermediate – aim to increase body mass by up to 1.5% / month

Advanced – aim to increase body mass by 1% / month

Body recomposition and sport

Just as there are cycles in training during which athletes focus on different goals, so too do we approach physical recomposition.
Strength and muscle are usually built in the off-season. And it is also a good time to lose weight, as a side effect of weight loss is increased fatigue.

It is essential for the athlete to determine whether they will benefit more from building strength and muscle mass or losing weight and adjust their approach accordingly. Since athletes usually have less body fat, it is advisable to focus on strength and muscle building. Often, in doing so, they will also reduce fat at the same time.


Timing of nutrition is important.

When training in the morning on an empty stomach, we don’t supply the body with energy when we are most active and when it needs it the most. Consequently, we take in a lot of energy later when we are less active. This difference can lead to poorer body composition. We may see weight loss, but much of that may be muscle mass.

As a result, even after losing weight, we may even end up having a higher percentage of body fat!

Another view of body recomposition:

When I focused on strength for 8 weeks, my weight stayed almost the same.

I increased muscle mass and strength in my legs, but lost muscle and strength in my upper body.

I explain it like this. Maintaining muscle mass is an energetically demanding process. Building new muscle requires even more energy.

I trained my legs much more than my upper body, which gave my body a strong signal to build muscle in my lower body.

By not taking in enough calories, my body prioritized recovery and building muscle in the lower body.

Which is right for you?

Do you have more than 30% body fat?

Choose body recomposition: Strength training + energy deficit.

Beginners usually have low muscle mass and focus on weight loss. As a result, they get a little lighter, and smaller and also lose what little muscle mass they have. Muscle mass is what creates the look, is essential for health, and allows for higher caloric intake. Even if your priority is to lose weight, it’s important to maintain and build muscle mass as well.

Do you have less than 15% body fat (men) / 20% women?

  • Less than 1 year time: bulk & cut cycle
  • Time doesn’t matter, I mainly don’t want to gain weight – body recomposition

Do you have trouble building muscle?

Focus on bulking. Many hard-gainers eat too little to gain muscle because they are afraid of gaining fat, and that leads them to make no progress.

You are a competitive athlete

In season: Focus on athletic performance, including strength training. The key is to maintain your strength, have enough energy for training, and avoid fatigue and injury.

During the off-season: It depends on what will benefit you more. Doing both is counterproductive. It’s very subjective here.

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