How Many Calories Over Maintenance Do You Need to Build Muscle?

The short answer: Most evidence points to a small surplus, roughly 5% to 20% above maintenance. For many people that is about 150 to 500 calories a day. A 2019 review advised starting near 360 to 480 kcal a day and adjusting from there. Larger surpluses mainly add fat, not extra muscle.

How big a surplus does the research support?

No study has pinned down one ideal number. That is the main finding of a 2019 review in Frontiers in Nutrition titled "Is an Energy Surplus Required to Maximize Skeletal Muscle Hypertrophy Associated With Resistance Training." The authors wrote that the specific surplus needed for muscle growth is unknown.

They did see clear evidence that a surplus supports growth. They also found that textbook advice often counts only the energy stored in new tissue. That math misses the energy cost of building muscle and the way your body adjusts to eating more.

Textbook figures range from about 1,500 to 2,000 kJ a day (about 360 to 480 kcal) for weight-stable athletes. They rise to about 4,000 kJ (about 960 kcal) for people who struggle to gain. The review advised a conservative start in the 1,500 to 2,000 kJ range. Then it advised regular checks of body composition and strength.

A 2019 review of off-season bodybuilding nutrition framed it as a percentage. It suggested a surplus of about 10% to 20% for novice and intermediate lifters. It set a target gain of about 0.25% to 0.5% of body weight per week. It advised advanced lifters to be more conservative.

Both approaches start from your maintenance intake. If you do not know yours, start with our guide on how to calculate TDEE. On a 2,500 kcal maintenance, a 10% to 20% surplus is 250 to 500 kcal a day.

Does a bigger surplus build more muscle?

Mostly no. Past a modest level, the extra calories go mainly to fat.

The clearest test is a 2023 randomized trial in Sports Medicine Open. Researchers assigned 21 trained lifters to maintenance, a 5% surplus, or a 15% surplus for eight weeks. COVID-19 cut the sample to 17 completers. The groups did not differ in muscle thickness or squat strength. The 15% group gained more bench press strength. It also gained more skinfold thickness, a marker of fat.

The authors concluded that faster weight gain, and by proxy larger surpluses, mainly increased fat gain. It did not add much muscle size or strength. The biceps, the most trained muscle in the study, may have benefited slightly.

An older trial in elite athletes found a similar pattern. Thirty-nine athletes added strength training for 8 to 12 weeks. One group followed a meal plan built for a calorie surplus. The other ate freely. The meal plan group ate more (3,585 vs. 2,964 kcal a day) and gained more weight (3.9% vs. 1.5%). Its fat mass rose 15%, compared with 3%. Lean mass gains did not differ between groups.

Do beginners need the same surplus as trained lifters?

No. Beginners can gain muscle faster, so they can use a somewhat larger surplus. Trained lifters gain slowly, so the same surplus leaves more fat behind.

That is why the off-season bodybuilding review gives its 10% to 20% range only for novice and intermediate lifters. It tells advanced lifters to pull the surplus and weekly gain lower. The Frontiers in Nutrition review lists training experience as one of the main reasons people respond differently. Age, sex, genetics, and starting body composition also matter.

New lifters also gain muscle with fewer conditions. In a 2002 trial, 73 men did eight weeks of resistance training. Two groups drank a supplement with about 2,010 extra kcal a day. They gained about 3 kg of fat-free mass, more than the control group. Strength rose by the same amount in all three groups. The authors noted that once protein needs are met, total energy has the largest effect on body composition.

Can you build muscle at maintenance or in a deficit?

Yes, in some cases. Gaining muscle while losing fat is often called recomposition.

In the 2023 trained-lifter trial, the maintenance group was not clearly worse for muscle thickness than the surplus groups. A surplus may help, but maintenance did not stop growth in that short study.

A deficit is harder. A 2022 meta-analysis pooled trials of resistance training in an energy deficit. Lean mass gains were smaller than in groups without a deficit. Strength gains were similar. Its meta-regression found that a deficit of about 500 kcal a day prevented lean mass gains.

Some people still gain under strict conditions. In a 2016 trial in the American Journal of Clinical Nutrition, young men ate about 40% below their needs for four weeks. They trained six days a week. The group eating 2.4 g of protein per kg gained 1.2 kg of lean mass and lost 4.8 kg of fat. The group eating 1.2 g per kg gained only 0.1 kg of lean mass.

If your main goal is to keep muscle while cutting, see our guide on preserving muscle in a calorie deficit.

How much protein goes with the surplus?

Protein matters as much as the surplus itself. The International Society of Sports Nutrition position stand on protein says 1.4 to 2.0 g per kg of body weight per day is enough for most exercising people. It also suggests 20 to 40 g per serving, spread every 3 to 4 hours.

A 2018 meta-analysis of 49 trials with 1,863 participants found a plateau. Total intakes above about 1.6 g per kg per day did not add further gains in fat-free mass. For an 80 kg (176 lb) person, 1.6 g per kg is about 128 g a day.

The bodybuilding review set a range of 1.6 to 2.2 g per kg. It suggested filling the rest of the surplus mostly with carbohydrate to support training. Our protein intake guide covers sources and timing. For evidence on protein powders and creatine, see supplements.md.

How do you know the surplus is right?

Track a few signals and adjust every few weeks. Both reviews stress checking body composition and strength, not just the scale.

• Body weight trend. Weigh daily or several times a week and use the weekly average. Aim for about 0.25% to 0.5% of body weight per week if you are newer to lifting. For an 80 kg person, that is 0.2 to 0.4 kg (about 0.4 to 0.9 lb).
• Waist measurement. A waist that grows quickly suggests the gain is mostly fat. In the Helms trial, weight gain predicted skinfold gain more strongly than muscle gain.
• Strength log. Record loads and reps for your main lifts. Steady gains over weeks suggest your intake supports training.
• Small adjustments. If weight rises faster than the target, trim intake a little. If it stalls for several weeks, add a little. The Frontiers review calls this ongoing personalization.

Daily weight swings come mostly from water and food in the gut, so judge the trend over weeks, not days.

The bottom line

A modest surplus of about 5% to 20% above maintenance fits the evidence for most lifters. That is roughly 150 to 500 kcal a day. Beginners can sit toward the top of that range, and trained lifters toward the bottom. Bigger surpluses mostly add fat. Pair the surplus with 1.6 to 2.2 g of protein per kg and steady resistance training, then adjust based on your weekly trend.

Last updated: October 2026. This article is for informational purposes only and does not constitute medical advice. Talk with a doctor or registered dietitian before changing your diet, especially if you have a medical condition or a history of disordered eating.