Macros for Muscle Gain: Protein, Carbs, and Fat Targets

Last updated: October 2026

Calories get you in the door for muscle gain, but macros determine how your body uses them. The same 3,000 calories split differently can produce very different results — more muscle, less fat, or the opposite.

This article covers the macro ratios that support muscle growth, how to set your individual targets, and the best food sources for each macronutrient.

The Macro Split for Muscle Gain

A solid starting point for a muscle-building phase:

• Protein: 30–35% of total calories
• Carbohydrates: 40–50% of total calories
• Fat: 20–30% of total calories

These are ratios, not rigid rules. The protein floor is the non-negotiable piece — everything else can flex based on preference and how your body responds.

Protein: The Non-Negotiable Macro

Protein is the raw material for muscle protein synthesis. Without adequate intake, your body can’t build new tissue regardless of how many calories you eat.

Target: 1.6–2.2g of protein per kg of body weight (0.7–1.0g per lb)

At the higher end of the range — 2.2g/kg — you’ll cover the needs of nearly everyone, even during hard training [1]. For most people lifting 3–5 days a week, 1.8–2.0g/kg hits the sweet spot.

Distribution matters too: spreading protein across 4–5 meals with 20–30g per meal maximizes muscle protein synthesis compared to having most of it in one or two sittings.

Best protein sources:

• Chicken breast, turkey, lean beef
• Salmon, tuna, white fish
• Eggs and egg whites
• Greek yogurt, cottage cheese
• Legumes (beans, lentils, chickpeas)
• Whey or casein protein powder

Carbohydrates: Fuel for Training Performance

Carbs are the primary energy source for resistance training. Muscle glycogen — stored carbohydrate — powers your sets. When glycogen is low, training intensity drops, and lower training intensity means a weaker growth stimulus.

Target: 45–50% of total calories from carbohydrates

This typically works out to 4–7g of carbs per kg of body weight, depending on training volume. Higher-volume training phases need the upper end; lower-volume phases can handle less.

Time your carbs around training when possible. A carb-rich meal 1–2 hours before training tops off glycogen. Carbs post-workout help replenish stores and support recovery.

Best carbohydrate sources:

• Rice, oats, quinoa
• Potatoes, sweet potatoes
• Fruits (bananas, berries, apples)
• Whole grain bread and pasta

Fat: Essential, Not Optional

Fat gets cut too aggressively in many muscle-gain diets. It’s a mistake. Dietary fat supports testosterone production, absorbs fat-soluble vitamins (A, D, E, K), and provides the structural foundation for cell membranes.

Target: 20–30% of total calories from fat

Going below 20% fat can suppress testosterone, which directly undermines muscle gain. Going above 30% isn’t harmful but means fewer calories available for carbs, which may compromise training performance.

Best fat sources:

• Olive oil, avocado oil
• Avocados
• Fatty fish (salmon, mackerel)
• Nuts and natural nut butters
• Eggs (whole)

Converting Ratios to Grams

Macro ratios are easier to track once you convert them to grams. Here’s how:

1. Protein and carbs = 4 calories per gram
2. Fat = 9 calories per gram

Example for a 2,800-calorie bulk (30% protein / 45% carbs / 25% fat):

Macro	Percentage	Calories	Grams
Protein	30%	840 cal	210g
Carbs	45%	1,260 cal	315g
Fat	25%	700 cal	78g

What About Total Calories?

Macros only work in context of your total calorie intake. Beginners, people returning to training, and those with more body fat can build some muscle even at maintenance or in a small deficit if protein is high (body recomposition). For experienced lifters, though, a modest calorie surplus makes muscle gain much easier and faster.

Get Your Macro Targets from the Bulk Calculator

Rather than manually working out the ratios, use the bulk calculator to get your calorie target and macro breakdown based on your weight, height, activity level, and goal rate of muscle gain.

Sources: [1] Morton RW, et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength. Br J Sports Med. 2018.