Macros for muscle gain: protein, carbs and fat for hypertrophy

Muscle hypertrophy requires two simultaneous conditions: adequate mechanical stimulus (resistance training) and a nutritional environment that favors net muscle protein synthesis. Macros for muscle gain differ substantially from those for fat loss, both in total calories and proportions.

The caloric surplus: enough but not excessive

To build muscle, the body needs a caloric surplus of 200–400 kcal/day above TDEE.^[1] This range balances:

• Providing enough energy to sustain muscle protein synthesis (MPS).
• Minimizing excess fat accumulation associated with a large surplus.

Larger surpluses (>500 kcal) slightly accelerate total mass gain but increase the fat-to-muscle ratio disproportionately. Beginners can tolerate a larger surplus (300–500 kcal) given their greater adaptive potential.

Protein: the limiting macronutrient for hypertrophy

A meta-analysis by Morton et al. (2018), analyzing 49 studies with 1,800 participants, concluded that the protein threshold for maximizing lean mass gains from resistance training is 1.62 g/kg/day, with an upper confidence interval of 2.2 g/kg/day.^[2] This means:

• Consuming less than 1.6 g/kg limits muscle gain even with optimal training.
• Exceeding 2.2 g/kg produces no additional benefit in healthy, trained individuals.
• The practical range is 1.6–2.2 g/kg/day, with the upper end for advanced athletes or during simultaneous caloric restriction (recomposition).

Protein targets by body weight

Body weight (kg)	Minimum (1.6 g/kg)	Optimal (2.0 g/kg)	Upper limit (2.2 g/kg)
60 kg	96 g	120 g	132 g
70 kg	112 g	140 g	154 g
80 kg	128 g	160 g	176 g
90 kg	144 g	180 g	198 g
100 kg	160 g	200 g	220 g

Carbohydrates: fuel for muscle glycogen

Carbohydrates are the preferred substrate during high-intensity training. Keeping muscle glycogen stores full enables:

• Greater training intensity and volume — the primary driver of hypertrophy.^[3]
• Reduced protein catabolism during exercise by providing available glucose.
• Promotion of post-training anabolic insulin signaling.

During a muscle-building phase, carbohydrates should represent 45–55 % of total calories, primarily from low-glycemic sources away from training (oats, brown rice, legumes) and moderate-to-high glycemic sources around training (white rice, potato, fruit).

Fat: the hormonal foundation of anabolism

Dietary fats — especially saturated and monounsaturated — are precursors to testosterone and other anabolic hormones. Restricting them excessively can suppress endogenous testosterone production. The recommended range is 0.8–1.2 g/kg/day or 20–30 % of total calories.

Timing: the anabolic window in perspective

The post-workout "anabolic window" exists but is wider than previously believed. Consuming 0.3–0.4 g of protein/kg within 2 hours of training is sufficient to maximize the acute MPS response, provided total daily protein intake is adequate.^[2] Distributing protein across 3–5 meals of 20–40 g throughout the day optimizes repeated MPS activation better than concentrating it in a few large meals.

To get your exact muscle-gain macro targets in seconds, our free macro calculator for muscle gain does all the maths for you.

Scientific references

1. Slater G, Phillips SM. Nutrition guidelines for strength sports: sprinting, weightlifting, throwing events, and bodybuilding. J Sports Sci. 2011;29(Suppl 1):S67-77. doi:10.1080/02640414.2011.574722
2. 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 in healthy adults. Br J Sports Med. 2018;52(6):376-384. doi:10.1136/bjsports-2017-097608
3. Schoenfeld BJ. The mechanisms of muscle hypertrophy and their application to resistance training. J Strength Cond Res. 2010;24(10):2857-2872. doi:10.1519/JSC.0b013e3181e840f3