How to Lose Fat and Build Muscle at the Same Time- Body Recomposition

Body Recomposition

How to Lose Fat and Build Muscle at the Same Time- Body Recomposition

“I’m trying to lose my stomach but gain muscle at the same time”

You’ve probably heard you need to eat in a calorie deficit to lose fat and eat in a surplus to build muscle.

But about when you don’t need to lose a lot of fat, but you want to gain some muscle, without gaining weight? Kinda like my coaching client Charlie did: 

This article is going to show you how you can do this too.

It’ll show you how to lose fat and build muscle at the same time in a process called body recomposition.

Body recomposition (or body recomp for short) works better for certain people than others. If you’re not looking to gain or lose weight, but want to improve the appearance of your body, then body recomposition is something to consider.

Body recomposition works especially well:

  • If you’re a total beginner to lifting weights
  • If you’re obese
  • If you have some experience training but have taken a long break for several months
  • If you usually do cardio and HIIT style workouts and have never focused on a proper strength training program before
  • If you have followed a weight training program in the past but never focused on heavy compound lifts
  • If you’re skinny fat and want to improve the appearance of your body
  • Any combination of the above

Body recomposition is all about timing as you’ll soon see.

Disclaimer: For all those technical people I know you don’t lose fat and build muscle at the exact same moment in time. Over the course of 6-12 months, if you follow these methods, you will be losing fat and building muscle without cutting and bulking, so it will seem like it is happening at the same time.

Building Muscle 101

Muscle growth happens when protein synthesis rates are higher than muscle protein degradation rates.

This is achieved primarily through resistance training. Muscle fibres are broken down and this signals to your body that it needs to increase protein synthesis to repair the muscle. 

Your body is super smart and will adapt to any stimulus you give it so that it can better cope with that stimulus next time. It fixes the broken down muscle fibres and also adds new ones so your muscles get bigger and stronger.

That’s why its so important to ensure you’re pushing yourself to get stronger in the gym! Each week, you should be aiming to increase your weight, or reps or sets (or decrease rest time) on at least a few of your main exercises.

Choose a program that emphasises compound movements like squats, deadlifts, chin ups and bench press. Isolation exercises can be included but the focus should be on getting strong in your compound lifts. 

Muscle growth is optimised by eating in a calorie surplus. It’s also important to get enough protein to provide the building blocks for new muscle tissue.

A surplus of 5%-15% over your maintenance calorie intake is adequate. The bigger the surplus of food, the more fat you’ll gain so there’s no need to go crazy.

Losing Fat 101

Fat loss comes down to energy balance.

After you eat, your body is digesting and absorbing nutrients. It has plenty of energy and is in fat storage mode.

Once everything is absorbed, your body shifts into fat burning mode so it has the energy required to stay alive.

Your body is either storing or burning fat at any given time.

Over the course of the day, if your body burns as much as it stores then it will stay the same. Fat loss occurs when it burns more than it stores.

In order for this to happen, you need to eat in a calorie deficit.

When you eat in a large calorie deficit, you’ll lose some muscle mass as well as fat. To maintain as much muscle as you can, it’s important to eat enough protein and also continue your weight training.

You can see why it’s hard to lose fat and build muscle at the same time. Protein is important for both, but calorie requirements are different.

Let’s welcome the star of body recomposition: Calorie Cycling.


Calorie Cycling 101

Calorie Cycling

Strawberry on Monday, chocolate on Tuesday and vanilla on Wednesday, then repeat. Calorie cycling is kinda like this but with calories instead of ice-cream flavours.

With calorie cycling you have higher calories on certain days of the week (usually training days) and lower calories on other days of the week (usually rest days).

If you’re doing a straight body recomp, your total calorie intake for the week will still be equal to your maintenance calorie total for the week.

If you want to do a “lean bulk” where you slowly focus on building more muscle with minimal fat gain you can be in a slight surplus for the week. In both cases you’ll still be eating more food on training days and less food on rest days.

Protein intake is kept constant on both days. Carbohydrate and fat ratios will differ. Your body is more likely to store fat as fat when in a surplus of calories, so fat is lower on training days (and carbohydrates are higher). Fat is essential to the body so to make sure you get enough, fat is higher on rest days (and carbohydrates are lower). In this way, calorie cycling is also a form of carb cycling.

Calorie cycling enables your body to go through brief moments of being in a deficit so you can lose fat and then a surplus so you can build muscle.

Overtime, you’ll build muscle and lose fat ‘at the same time.’

Note that this is an incredibly slow process since the deficits and surpluses are short lived. Results will happen slower than what they would in a traditional cut and bulk cycle (where you stay in a deficit or a surplus for weeks at a time).

How to set up your calorie targets

To get your total weekly maintenance calories you need to work out your daily maintenance calorie intake (see my article here for help with that) then multiply it by 7 days.

Now you need to divide this total weekly intake of calories into training day and rest day calories.

On training days you want to eat in a slight calorie surplus and on rest days you want to eat in a slight deficit.

For a straight body recomp you can start with a 20% surplus on training days and a 20% deficit on rest days. You can alter these to suit your situation best. For example, a 15% surplus on training days and a 40% deficit on rest days might be better if you’re on the fat side of skinny fat and want an overall deficit for the week (a body recomp with a slow cut).

Let do an example…

Say your maintenance calories are 2000 calories per day. This is 14000 calories per week.

To workout your training day and rest day calorie targets:

A 20% surplus or deficit would be 400 calories. If you’re training 3 days per week and resting 4 days then you’d have a surplus of 1200 cals (for training days). This needs to be split into 4 rest days which results in a deficit of 300 calories on those days. The week would look like this:

Monday (Training): 2400 cals

Tues (Rest): 1700 cals

Wed (Training): 2400 cals

Thur (Rest): 1700 cals

Fri (Rest): 1700 cals

Sat (Training): 2400 cals

Sun (Rest): 1700 cals

Total Weekly Calories: 14000 cals

The total weekly calorie intake is equal to your total maintenance calories for the week. So we don’t expect weight loss or weight gain overall.

To work out your protein, carb and fat breakdown for training and rest days:

Say you weighed 130 pounds, your macros would look like this:

Training day macros:

Calories: 2400

Protein: 130 x 1 = 130grams

Fat: 2400 x 20% = 480 cals of fat. 480/9= 53grams

Carbs: 2400 – (130 x 4) – (53 x 9) = 1403 cals of carbs = 350grams

Rest day macros:

Calories: 1700

Protein: 130 x 1 = 130grams

Fat: 1700 x 40% = 680 cals of fat. 680/9= 75grams

Carbs: 1700 – (130 x 4) – (75 x 9) = 505 cals of carbs = 126grams


Timing is everything, including rest time!

Recovery is crucial for muscle repair and growth. You need to make sure you’re taking your rest days.

This means getting enough sleep and limiting cardio. Do not fill up non-training days with excessive cardio!

Rest days are also crucial for calorie cycling since you’ll be eating less on these days. If you workout 6 days a week and eat in a surplus on training days then you’ll barely be spending any time in a deficit and fat loss won’t happen.

The hardest part of body recomposition…

You might think the calculations for calorie cycling are difficult.

What’s more difficult is trusting the process and sticking to your training and nutrition plan.

You’re not going to see progress week by week.

To accomplish body recomposition, you need to have a long term vision, extreme patience and discipline.

If you are likely to get discouraged from not being able to see progress each week, or if you suck at waiting games, it might not be the right approach for you.

If you would like specific guidance based on your body, click here to apply for my online coaching program.