Building muscle or losing body fat can be a daunting enough process on its own—so, understandably, achieving both at the same time can seem downright impossible.
After all, the strategy for building muscle is typically the opposite of the strategy for losing fat. Muscle gain—or any sort of weight gain, for that matter—occurs when your body has more building materials (a.k.a. calories and nutrients) than it needs for basic upkeep, and adds to your body’s structures (like muscles and fat stores), explains Craig Primack, M.D., president-elect of the Obesity Medicine Association. Weight loss, though, happens when your body is short on materials and starts demo-ing your body’s structures for scrap parts to use.
That’s why, when we lose weight, we never lose 100 percent fat, but a mix of fat, water, and muscle, explains Denver-based dietitian Jessica Crandall, R.D., C.D.E., a spokesperson for the Academy of Nutrition and Dietetics. In fact, up to 20 percent of that weight loss can come from muscle, as our body repurposes those proteins for other things. On the flip side, it’s also impossible to gain 100 percent muscle; usually some fat comes along with it, too. “You can’t eat a chicken breast and tell your body to store all of it in your biceps,” she says.
While it’s way easier to make major muscle gains if you’re okay with putting on a bit of fat in the process—and to lose a significant amount of weight when you’re just trying to preserve muscle—the two-for-one combo is possible! “You can gain some muscle and lose quite a bit fat at the same time,” says Sarah Walls, C.S.C.S., owner of SAPT Strength & Performance Training in Virginia.
You just need a very specific strategy: One McMaster University study, for example, found that guys were able to gain about 2.64 pounds of muscle and lose 10.56 pounds of fat in four weeks given the right training and nutrition plan (which turned out to be workouts focused on strength training and HIIT, and a high-protein, calorie-restricted diet).
Below, the experts break down the dos and don’ts of gaining muscle and losing fat at the same time.
DON’T: Focus On Cardio
Cardiovascular exercise, especially steady-state cardio, doesn’t stress your muscles enough to stimulate much of an increase in muscle size (called ‘hypertrophy’), says Walls. Over time, doing cardio alone will just increase how much of the weight you lose comes from muscle mass.
To build muscle, which boosts your metabolism and makes fat loss easier, “your training plan should be biased toward free-weight, full-body compound movements like squats and pullups,” says Walls. Since these moves engage large muscle groups, not only do they support muscle gains, but also blast a ton of calories in the process.
For maximal hypertrophy, try to work each major muscle group at least twice a week and include squats, hip-hinges (like deadlifts), pushing exercises (like pushups or chest presses), and pulling exercises (like bent-over rows and pullups) in your workouts.
Just in case you’re not sold: One Harvard School of Public Health study found that guys who performed 20 minutes of resistance training per day gained less abdominal fat over the course of a decade than to those who did the same amount of cardio.
DO: Integrate HIIT
If you are going to do cardio, make it high-intensity interval training, which alternates between bouts of all-out effort and low-intensity recovery, and has been shown to support both muscle gain and fat loss. How? HIIT burns major calories, improves your insulin sensitivity, and boosts your muscles’ abilities to use both sugar and fat as fuel, according to one Journal of Obesity review. In fact, one Journal of Strength and Conditioning Research study found that just one month of HIIT training helped rowers decrease their body fat percentage, while traditional rowing had no effect.
DON’T: Drastically Cut Calories
The greater your caloric deficit, the more likely your body is to start catabolizing (breaking down) muscle for energy and other biological necessities, says Crandall. As a general rule, experts say a 500-calorie deficit—achieved through diet, exercise, or a combination of the two—is best for moderate weight loss.
That said, if you’re really vying for muscle gains, that 500-calorie deficit may be too much—especially if you want to go hard in the gym. In this case, Crandall recommends sticking to a caloric deficit as small as 300 (or even fewer) calories per day. Regularly measuring your body fat percentage can help you determine how much of a caloric deficit you need to reach your goals. (The scale can’t tell you how much of your weight comes from lean versus fat mass.)
One word of warning: Consuming the right number of calories is important, but focusing on calories alone doesn’t guarantee your body gets the carbs it needs to lift heavy weights, the protein it needs to recover from those lifts, or the fat it needs to maintain healthy hormone function, Crandall says.
DO: Balance Your Macros
The real key to simultaneous building and shredding is protein, which supports muscle mass even when calories run short. Though the current recommended daily allowance (RDA) for protein is 0.8 grams per kilogram of your body weight per day, that recommendation is the absolute minimum, not the ideal—especially when it comes to muscle-building, explains Crandall. One American Journal of Clinical Nutrition study found that men who ate 2.4 grams of protein per kilogram of body weight per day for four weeks lost about three more pounds of fat—and gained two more pounds of muscle—than men who ate 1.2 grams of protein per kilogram of body weight per day.
The International Society of Sports Nutrition recommends between 1.6 and 2.2 grams of protein per kilogram of body mass per day for optimal muscle growth. That’s between 131 and 180 grams per day for a 180-pound adult.
When it comes to carbs and fats, Crandall recommends a relatively balanced approach. Most adults need a baseline of roughly 130 grams of carbs—which not only fuel exercise, but also help shuttle protein into your muscles—per day, plus another 40 to 60 grams for every hour of intense exercise (like heavy strength training) they do. Fats can make up anywhere between 15 and 30 percent of your total daily calories, depending on how much you need to feel satiated.
DON’T: Eat Your Protein All At Once
Hitting your daily protein goals is important, but, if like most Americans you get the vast majority of your protein at dinner, you’re essentially depriving your muscles of the building blocks they need all day long only to then give them more than they can handle in a single sitting, says Crandall. The result: Your muscles waste—or at least don’t grow optimally—throughout most of day, and the excess protein you eat at dinner gets stored as fat.
A 2018 review published in the Journal of the International Society of Sports Nutrition suggests that people should consume 0.4 to 0.55 grams of protein per kilogram of their body weight at each and every meal (it recommends four per day) for optimal muscle growth. That’s 33 to 45 grams of protein four times per day for that same 180-pound adult.