Weight Training on a Calorie Deficit

Cardio might not be the best form of exercise when you're on a diet.
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Lifting weights is typically associated with bulking up and getting stronger, not slimming down. However, lifting heavy on a calorie deficit is not only possible, but it's important if you want to keep your hard-earned muscle and strength.


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Achieving a Calorie Deficit

Reducing your calories to lose weight or for other health reasons can be challenging. To lose weight, you have to create a calorie deficit, which means you must eat fewer calories than you burn. You can achieve a calorie deficit through diet, exercise or both.

If you decide to eat less to achieve a calorie deficit, it will work as long as you're actually taking in fewer calories than you're burning. To figure out how many calories you need each day, use a diet tracking app, which gives you an estimate of how many calories you should eat when you want to lose weight. You can also log your food and track your daily calorie intake.


Exercising to achieve a calorie deficit is more complicated. It's hard to track how many calories you burn in a workout because there are many factors involved, such as the intensity of your workout and the size of your body.

Combining exercise and diet seems to be the best method, particularly if you lift weights. When you're in a calorie deficit you're also more likely to lose muscle mass, according to an October 2018 review published in Nutrients.


If you start eating less, you're most likely consuming less protein, which gives your body less protein to build muscle with. You're also using muscle for energy more than usual because your body has to get it from places other than food.

Read more: Calories Per Day to Lose 3 Pounds Per Week

Calorie Deficit and Weight Training

Food supplies nutrients and energy to power you through a workout. When you eat less, you have less energy available. While you might feel lighter on a calorie deficit from eating less and losing weight, don't expect to hit any record numbers. Your performance in the gym can increase, but it's going to be difficult without extra energy.


Your weightlifting routine doesn't necessarily need to change if you're dieting to achieve a calorie deficit. Continue whatever program you were already on, making sure that it hits all the desired body parts.

When you're in a calorie deficit, powerlifting is a training style that can make your life easier. It consists of compound movements that hit multiple muscle groups at once, meaning you can do fewer exercises.


Powerlifting involves three main movements: bench press, squat and deadlift. Between those three movements, you'll work the major muscles of your legs and upper body. You'll need a barbell for all three movements, and it's best to hire a coach or trainer to show you proper technique. Because you'll lift heavy weights, there's an increased risk for injury.

Powerlifting is a straightforward and simple way to train, which makes it attractive if you're working out while in a calorie deficit. If you have less energy, you might be less motivated to train. It's important to keep going to the gym, because lifting heavy on a calorie deficit helps preserve your hard-earned muscle mass.


Lifting Weights Preserves Muscle Mass

Weight training works the muscles, so it might seem like lifting weights in a calorie deficit would actually hurt the muscles — but the opposite is true. Lifting weights while in a calorie deficit actually helps maintain lean mass.

An April 2018 research review published in Nutrients found that lifting weights preserved roughly 93 percent of muscle mass in subjects who were dieting to lose weight. The subjects lifted weights three times per week and consumed only 15 percent of their calories from protein, which is low for a calorie deficit.


The results of the study indicate that lifting weights can preserve muscle mass during a caloric deficit — even if you don't increase your protein intake. The subjects still lost body fat, even though they preserved muscle. Many who lose weight do it to look better. Preserving muscle mass helps keep your body looking muscular and toned.

A separate study examining the same question had the same findings. In January 2018, the study was published in Human Kinetics and had three groups of subjects: no change, diet only and diet plus weightlifting.


The weightlifting group actually gained muscle, even though they were on a diet. However, they were given 3.1 grams of protein per kilogram of body weight per day, which is a high amount and helps build muscle.

Read more: 13 Benefits of Weightlifting That No One Tells You About

Eat More Protein

It's scary to think that you can lose your hard-earned muscle mass by dieting, but you can preserve it if you up your protein intake. High-protein diets and weightlifting go hand in hand. This is the most important macronutrient if you want to build or preserve muscle.

After ingestion, protein is broken down into amino acids, which are its building blocks. Your body reassembles those amino acids to build muscle and other tissues.

The normal recommended intake for protein is 0.8 grams per kilogram of body weight, according to a March 2018 review published in Human Kinetics. However, when you're in a caloric deficit, you need a lot more protein to prevent muscle loss. You can even gain some muscle while in a caloric deficit, especially if you're new to exercise.

A June 2017 article published in the Journal of the International Society of Sports Nutrition explains that athletes who are in a caloric deficit may need between 2.3 and 3.1 grams of protein per kilogram of body weight to prevent loss of muscle mass.

Eating more protein can actually make it easier to eat fewer calories. Protein has a satiating effect, which means it keeps you feeling full longer than many other foods that are low in nutrients. A June 2015 review published in the American Journal of Clinical Nutrition showed that eating a higher protein diet, with between 1.2 and 1.6 grams of protein per kilogram of body weight, reduces appetite and helped subjects manage their weight.

While it's possible to eat too much protein, the amount you need to eat to see adverse effects is quite high. According to a March 2016 study published in Food & Function, eating 3.5 grams of protein per kilogram of body weight was the highest possible healthy intake. The researchers also note that those subjects were well-adapted, meaning they were used to a high-protein diet.