How to Keep Muscle While Losing Fat

Is it possible to keep muscle when cutting body fat? We separate the fact from the fiction.

First, let’s dispel some myths. 

• It’s impossible to turn fat into muscle, no matter how much we all wish we could. 
• Cardio isn’t the only way to shed calories, but it’s not a bad place to start. 
• And to lose more fat and build more muscle, just training harder is rarely the answer.

When it comes to building muscle and shifting body fat, these are common misconceptions among gym-going circles. Another is that in order to build a strong, lean body, you must first bulk, then cut. That might be the way competition bodybuilders do it but it’s certainly not the only way.

In fact, it’s entirely possible to keep most of your hard-earned muscle while cutting body fat, and it’s also possible to achieve this year-round in a healthy, sustainable way. 

Here we explore exactly how. 

The mechanics behind cutting

“Cutting – or shredding – is just another word for fat loss,” says Daniel Clarke, registered nutritionist and junior sustainable nutrition manager at Huel. “Fundamentally, fat loss occurs when we are in what’s known as a calorie deficit when we consume fewer calories than our body requires.”

In this state, there are not enough calories in our diet to fuel daily activity and regular cell function, so instead, we draw on energy reserves stored in the body as fat and muscle.

When fat is used, triglycerides are broken down and sent to the mitochondria to produce adenosine triphosphate, which you might know better as ATP, the body’s primary energy currency. 

This process, known as beta-oxidation, also results in carbon dioxide and water as by-products that are breathed out and excreted in our urine and sweat.

“Ideally we want to lose fat rather than muscle because this is healthier,” says Clarke. “It may aid athletic performance and, aesthetically, it tends to produce favourable results too.” 

Muscle building mistakes when cutting fat

One of the most common traps people tend to fall into when cutting body fat is going cold turkey on their diet and plunging themselves into too great a calorie deficit. 

“Due to the sudden drop off in available energy, the body will turn to skeletal muscle as an emergency fuel source, which can cause rapid muscle loss,” Clarke explains. 

To be on the safe side, he says, you should aim to reduce your daily intake by around 500 calories, or 10-20 percent of your total calorie needs per day, and use a meal tracking app like MyFitnessPal as a guide.

“Another common mistake when trying to lose fat is cutting out an entire food group altogether,” says Brett Starkowitz, Master Trainer and Head of Education at Ten Health & Fitness.

Eliminating fats and carbohydrates from your diet can deny your body vital nutrients – especially when exercising.

“Consuming moderate amounts of complex carbohydrates like sweet potatoes, oats and rice will help your muscles recover and refuel,” says Starkowitz. “Nutritious fats found in milk, eggs and oily fish are also essential for the absorption of vitamins and to support healthy brain function.”

Protein, unsurprisingly, is also crucial. 

Diets that consist of between 1.2-1.6g of protein per kilogram of body weight per day, including at least 25-30g of protein per meal, have been shown to be beneficial for appetite control, body weight management and to reduce cardiometabolic risk factors.  

How to keep your muscle mass while cutting fat

So, to keep muscle when cutting, you should reduce your calorie intake moderately while still consuming complex carbs, healthy fats and plenty of high-quality protein. 

That’s your diet taken care of, but what about supplements? And how about exercise? Here we’ve outlined five more tried-and-tested tips from our experts to help you cut fat without losing muscle.

1. Crank up the cardio

“When structuring a workout program for fat loss, the goal is to elevate your heart rate and stimulate muscle growth,” says Starkowitz. Cardiovascular exercise is a great place to start. But think short to medium bursts and sprints rather than marathon slogs. 

Finding a balance between High-Intensity Interval Training (HIIT), mixed in with some Low-Intensity Steady State (LISS) cardio, like steady running or cycling, should trigger the right results. “The key here is sustaining an elevated heart rate for 45-60 minutes per session,” he adds. 

2. Keep your muscles guessing

While cardio is a no-brainer for fat loss, resistance training is crucial if you want to maintain – and enhance – your hard-won muscle mass. Four to five times a week is optimal, according to Starkowitz.  

“You should vary your strength training too,” he says. “Use a combination of multi-joint compound movements like squats, deadlifts, pressing exercises and rows, and mix up the load, sets, reps and tempo to keep your body challenged.” 

3. Use supplements sparingly

Beyond a healthy, varied diet, Clarke doesn’t suggest relying too heavily on supplements like weight loss formulas or pre-workout shakes. However, he says, two deserve a special mention.

“Caffeine, in the form of pre-workout supplements, can aid muscle-building efforts in the gym,” he explains. “Creatine, which is one of the most well-studied supplements in the sports world, can provide similar training benefits. It may initially appear to hinder cutting results because it leads to more water being held by the body, but this is only temporary.”

4. Be patient

When it comes to your health and fitness, shortcuts are rarely the answer. Instead, patience is your friend. “Be realistic – allow yourself a minimum of 12 weeks to achieve your cutting goal,” advises Starkowitz. 

“At a moderate calorie deficit, your aim should be to drop approximately 1% of your body weight per week to preserve as much muscle mass as possible.” But remember, muscle mass weighs more than fat so don’t be disappointed if the number on the scales isn’t shifting as fast as you’d like. 

Instead, use progress photos and your performance in the gym as a barometer of success. 

5. Eat, sleep, train, repeat

Finally, both Clarke and Starkowitz espouse the age-old mantra of consistency. That goes for your diet, your training and especially your recovery. “Overtraining and injury is a common risk when cutting, especially if on reduced calories,” says Starkowitz.

“To safeguard your success, schedule in active recovery days between your most taxing workouts and get plenty of sleep to restore your energy levels.”

“Don’t be disheartened if it’s slow going,” adds Clarke. “The reason people go through cutting and bulking phases is because it's really hard to lose fat and gain muscle at the same time.” But with a patient, consistent approach anything is possible. 

(Just not magically turning body fat into rippling muscle, sadly.) 

Words: Sam Rider