How much protein to build muscle, and how to split it across meals

Training builds the muscle. Food gives it something to build with. Protein is the piece most people under-plan, either too little overall or squeezed into one big dinner. Here’s how much the research supports and how to spread it out.

How much protein do I need to build muscle?

Most people who lift do well with about 1.6 to 2.2 grams per kilogram of body weight a day.

The International Society of Sports Nutrition suggests 1.4 to 2.0 g per kg a day for most people who exercise. A 2018 meta-analysis of 49 trials, published in the British Journal of Sports Medicine, found that extra protein stopped adding lean mass at around 1.6 g per kg a day. The statistical range around that point reached about 2.2 g, so the authors suggested up to 2.2 g for people who want to cover every base.

Does it matter more for some people?

Yes. In the same meta-analysis, extra protein helped more in people who already trained, and less as age went up.

That doesn’t mean older adults should skip it. It means training matters a great deal, and protein works best alongside it.

How should I split it across meals?

Aim for about 0.4 g per kg at each meal, across at least four meals.

That’s the suggestion from a 2018 paper by Brad Schoenfeld and Alan Aragon in the Journal of the International Society of Sports Nutrition. The ISSN position stand says something similar: 20 to 40 g per serving, spread evenly every 3 to 4 hours.

The protein calculator works out your own split.

Is there a limit to how much protein one meal can use?

Not a hard one.

The old idea was that the body can only use about 20 to 25 g at a time. Schoenfeld and Aragon’s review found that larger doses aren’t simply wasted, and some of the extra still goes toward building tissue. Spreading protein out is still the easiest way to reach a high daily number.

Does timing around my workout matter?

Less than the daily total.

The ISSN says benefits come from protein eaten before or after training, and the effect of a workout on muscle lasts for many hours. A normal meal within a few hours either side is plenty.

What does 30 grams look like?

A palm-sized piece of chicken, or a mix of two smaller foods.

Rounded USDA FoodData Central values. Your label is the final word.

Two eggs with ¾ cup of Greek yogurt is about 30 g. So is 3 oz of tuna with two eggs in a salad.

How much training goes with it?

Muscle-strengthening work for all major muscle groups on at least 2 days a week.

That’s the floor in the Physical Activity Guidelines for Americans. Most people building muscle train more often. Without the training, extra protein has little to work on.

How does Imi help?

On the build muscle goal, Imi sets protein at 1.8 g per kg a day and splits it across your meals so each one does some work.

It adds a small calorie surplus above maintenance, capped at 15%, so you’re not eating far past what you use. Imi reads your workouts from Apple Health and counts your strength sessions toward 3 a week. If your scale writes lean mass to Apple Health, Imi shows that too. Imi plans food, not workouts.

Try the protein calculator, or see how Imi plans for building muscle. On a budget? Read high-protein meal prep on a budget.