How to Keep Muscle While Losing Fat

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

• To lose more fat and build more muscle, rarely the answer is “just train harder.” 

When it comes to building muscle and shifting body fat, these are common misconceptions among gym-going circles. Another is that 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.

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

“The term “cutting” is another word for fat loss,” says Madeline Peck, RDN, CDN on the Huel nutrition team. “If your goal is to preserve lean muscle mass while losing fat, both a moderate calorie deficit (burning more calories than we consume) & ensuring adequate protein intake is important.” 

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.

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. 

“When a calorie deficit is too significant, it can have negative effects on metabolism, muscle loss, and can make it difficult to meet our nutrient needs,” Peck says. 

“A deficit of 250 to 500 calories per day can result in 0.5-1 lb of weight loss per week, but it is important to do what is most sustainable and feasible,” Peck explains. A dietitian can also help make individual recommendations to support your journey."

“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) and 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, Peck doesn’t suggest worrying too much about supplements regarding fat loss. One, however, deserves a shout-out.

"Creatine is a well-studied supplement that can help provide you with more energy during your workout, especially for weight lifting and recovery,” Peck says. “It also may have some neuroprotective properties, so it could have benefits beyond the gym.” 

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 at least 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 Peck 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 active recovery days between your most taxing workouts and get plenty of sleep to restore your energy levels.”

Don’t be disheartened if progress is happening slowly, either. With a patient, consistent approach anything is possible. 

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

Words: Sam Rider