Protein for lifters: how much, and why bodyweight is the wrong anchor
A lifter needs about 1.4-2.0 g of protein per kg of bodyweight per day (ISSN), with muscle gains levelling off around 1.6 g/kg. Eat it as 3-5 meals of 0.25-0.3 g/kg, every 3-4 hours. Keep it the same on rest days, and set it from lean mass if you carry more fat.
This post is about how to use that number: how to split it, when to eat it, and what changes on lifting days. If you want the case for anchoring to lean mass rather than scale weight, it’s in why protein should track lean mass, not bodyweight.
How much protein does a lifter need per day?
The answer is 1.4-2.0 g per kg of bodyweight per day. The ISSN position stand on protein and exercise (Jäger et al., 2017) gives 1.4-2.0 g/kg/day as enough for most people who exercise. The ACSM, AND and Dietitians of Canada joint position on nutrition and athletic performance (Thomas, Erdman and Burke, 2016) gives 1.2-2.0 g/kg/day.
There is a ceiling on what extra protein buys. A 2018 meta-analysis of 49 trials (Morton et al.) found that gains in fat-free mass from resistance training stopped improving above about 1.6 g/kg/day. Past that point, more protein mostly displaces carbs.
Why is bodyweight the wrong anchor for a lifter?
Because fat mass doesn’t need protein, and bodyweight can’t tell fat from muscle. The ISSN, joint-position and Morton figures are per kg of bodyweight, drawn mostly from trained people. Two lifters at 85 kg can carry very different amounts of muscle. The deficit range from Helms et al. (2014) is stated per kg of fat-free mass: 2.3-3.1 g/kg.
Sweatmeal and our lean-mass post use 1.6-2.2 g per kg of fat-adjusted weight. That is our working range informed by these sources, not a figure any one of them states.
How should a lifter split protein across the day?
Eat 3-5 roughly even doses of 0.25-0.3 g/kg, about 3-4 hours apart. The ISSN gives an effective dose as 0.25 g/kg of bodyweight, or 20-40 g. The joint position gives 0.25-0.3 g/kg, or 15-25 g.
That works out to:
- Breakfast: one dose.
- Lunch: one dose.
- Post-training meal: one dose.
- Dinner: one dose.
- Optionally, before bed: 30-40 g of casein. The ISSN reports that this raises overnight muscle protein synthesis.
Spreading it out beats loading it at dinner, because each meal triggers its own round of protein synthesis.
Does protein timing around the workout matter?
It matters less than the daily total and the even split. The joint position recommends about 0.3 g/kg of high-quality protein after key sessions. In practice your next regular meal often covers it. If you train fasted early in the morning, eating soon after the session matters more because the previous dose was hours ago.
Should protein change on training days and rest days?
No. Keep protein the same and let carbs move. Repair carries on after the session ends, so a rest day is not a day off for muscle. Both the ISSN and the joint position give protein as a steady daily amount, not one tied to the session.
What should change is carbohydrate. The joint position’s daily carb ranges scale with training load:
- Light or skill work: 3-5 g/kg.
- About an hour of moderate training a day: 5-7 g/kg.
So a heavy leg day earns more carbs than a rest day. Protein stays on the same number.
What does this look like for an 85 kg lifter?
Take an 85 kg lifter at 18% body fat:
| Step | Calculation | Result |
|---|---|---|
| Lean mass | 85 × (1 - 0.18) | 69.7 kg |
| Daily protein, maintenance | 69.7 × 2.0 g | about 139 g |
| Same factor on bodyweight | 85 × 2.0 g | 170 g |
| Per meal, 4 meals | 139 ÷ 4 | about 35 g |
| ISSN minimum per dose | 85 × 0.25 g | about 21 g |
| Cut range (Helms) | 69.7 × 2.3 to 3.1 g | about 160-216 g |
The bodyweight anchor gives 31 g more a day than the lean-mass anchor, or about 124 kcal that could go to carbs. The lean-mass figure of 139 g is still 1.64 g per kg of bodyweight, which is at the point where Morton’s meta-analysis saw gains level off. Four meals of about 35 g each clear the per-dose minimum with room to spare. In a cut, his protein climbs, but from the lean-mass base, not from 85 kg.
These ranges come from position stands and reviews, not from a measurement of you. Individual response varies, so treat them as a starting point and adjust from progress.
How Sweatmeal handles this
Sweatmeal sets protein per kg of your fat-adjusted weight: your lean mass if you’ve entered a body-fat percentage, otherwise an estimate from your height. Protein stays put day to day, while carbs flex with your training load, and protein ramps up as a deficit deepens. You can also tune the protein-per-kg coefficient yourself. The calculations are on the methodology page.