To build muscle, aim for roughly 1.6 to 2.2 grams of protein per kilogram of body weight per day and 4 to 7 grams of carbohydrates per kilogram of body weight per day. For a 180-pound (82 kg) person, that works out to about 130 to 180 grams of protein and 330 to 570 grams of carbs daily. These ranges give you room to adjust based on your body size, training intensity, and goals.
How Much Protein You Actually Need
The strongest evidence points to 1.6 g/kg/day as the threshold where muscle growth benefits from additional protein start to level off. A large meta-analysis found that protein intake beyond this point didn’t produce significantly more muscle when combined with resistance training. That said, intakes up to 2.2 g/kg/day still fall within the confidence interval, meaning some people may benefit from going higher.
The International Society of Sports Nutrition recommends 1.4 to 2.0 g/kg/day for physically active individuals, with strength and power athletes at the upper end of that range. In practical terms, here’s what that looks like:
- 150 lb (68 kg) person: 109–150 g protein per day
- 180 lb (82 kg) person: 131–180 g protein per day
- 200 lb (91 kg) person: 145–200 g protein per day
If you’re newer to lifting, you can likely build muscle toward the lower end of these ranges. If you’ve been training for years and gains come slower, pushing toward 2.0 or even 2.2 g/kg/day is reasonable.
How to Spread Protein Across the Day
Your body doesn’t use protein in unlimited quantities at once. Research consistently shows that about 20 to 25 grams of high-quality protein per meal maximally stimulates muscle protein synthesis in most people. A more individualized target is 0.4 g/kg per meal across at least four meals, which lands you at the 1.6 g/kg daily minimum. If you’re aiming for the upper range of 2.2 g/kg/day, that’s roughly 0.55 g/kg per meal over four meals.
Spacing meals about three hours apart appears to keep muscle-building signals elevated throughout the day. You don’t need to eat every hour or obsess over exact timing, but eating all your protein in one or two meals likely leaves gains on the table. Three to five protein-rich meals spread across the day is a solid framework.
What About Plant-Based Protein?
Plant proteins are generally lower in certain essential amino acids and less digestible than animal proteins, which has led to concerns about muscle-building potential. A meta-analysis of randomized controlled trials found that animal protein produced a small but statistically significant advantage in percent lean mass compared to plant protein. However, when total protein intake was adequate, the difference in absolute lean mass was not statistically significant.
If you eat a varied diet that includes different plant protein sources (legumes, grains, soy, seeds), you can meet your muscle-building needs without animal products. Some researchers suggest eating slightly more total protein to compensate for lower digestibility, so aiming toward the higher end of the range (closer to 2.0–2.2 g/kg/day) is a practical strategy for plant-based eaters.
How Many Carbs for Muscle Growth
Carbohydrates don’t directly trigger muscle protein synthesis the way protein does, but they play a supporting role that’s easy to underestimate. Recommendations for strength athletes typically fall between 4 and 7 g/kg/day, though some older guidelines suggest up to 8 to 10 g/kg/day for heavy anaerobic training. Most people building muscle will do well in the 4 to 7 range.
Carbs matter for two main reasons. First, they fuel your training. Your muscles rely on stored glycogen during resistance exercise, and depleted glycogen means lower intensity, fewer reps, and less total work. Second, carbohydrates reduce muscle protein breakdown after training. One study found that consuming carbohydrates after resistance exercise increased muscle protein synthesis by 36% compared to just 6% in a placebo group, while also lowering markers of protein degradation. The net effect was a more positive protein balance.
That said, carbs don’t need to be precisely timed the way many people think. Evidence suggests that meeting your total daily carbohydrate goal matters more than worrying about exact post-workout doses. If you train with high volume (eleven or more sets per muscle group) or have two sessions in the same day targeting the same muscles, prioritizing carbs soon after training helps replenish glycogen faster.
Putting the Macros Together
A commonly cited macronutrient split for muscle building is roughly 55 to 60% of calories from carbohydrates, 25 to 30% from protein, and 15 to 20% from fat. These percentages align well with the gram-per-kilogram targets when you’re eating in a slight calorie surplus.
Speaking of surplus: you need to eat more calories than you burn to maximize muscle growth. Research from Frontiers in Nutrition recommends starting conservatively with a surplus of roughly 360 to 480 calories per day (1,500 to 2,000 kilojoules). This is enough to support muscle building without piling on unnecessary body fat. If you gain mostly fat at this level, scale back. If you’re not gaining at all, increase slightly.
Here’s a sample daily breakdown for a 180-pound (82 kg) person aiming for moderate muscle gain:
- Protein: 145–180 g (580–720 calories)
- Carbohydrates: 330–490 g (1,320–1,960 calories)
- Fat: 55–75 g (495–675 calories)
- Total: roughly 2,400–3,350 calories depending on activity level
What Matters Most
If you take one thing from the numbers above, let it be this: hit your daily protein target first. Protein is the only macronutrient that directly drives muscle repair and growth. Get at least 1.6 g/kg/day, split across four or more meals with 20 to 40 grams each.
Carbohydrates are next in priority. They keep your workouts productive and help limit muscle breakdown. Fill the rest of your calories with carbs and a moderate amount of fat. Monitor your body composition over weeks, not days. If you’re gaining strength and your weight is creeping up by roughly 0.25 to 0.5% of body weight per week, your nutrition is working. Adjust the numbers up or down based on what you see in the mirror and on the scale over time.