Daily protein intake that maximises .
Pooling 49 randomised trials of 1,863 lifters, extra protein reliably built more muscle — but only up to about 1.6 g per kilo of bodyweight per day. Beyond that, more protein did not mean more muscle.
What the researchers did
Morton and colleagues meta-analysed 49 randomised controlled trials comparing higher- vs lower-protein diets in people doing resistance training. They looked at fat-free mass, 1-rep-max strength, and how the response changed as intake climbed.
The key finding
Extra protein produced consistent gains in lean mass and strength — but the curve flattened at roughly 1.6 g/kg/day. Above that, adding more protein did essentially nothing for . Older lifters and heavier trainees needed to push toward the top of the 1.6–2.2 g/kg range to overcome .
Why it matters
You do not need heroic shakes or 300 g days. A 70 kg lifter hitting ~112 g of protein spread across 3–4 meals is inside the muscle-building sweet spot. Above 2.2 g/kg you are paying for expensive urine.
Bodyweight (kg) × 1.6 to 2.2 = your daily protein floor and ceiling for . Split across 3–4 meals of ~0.4 g/kg each.
- 7–9Nightly sleep for recovery, hormones and growth hormone release.
- 8,000Daily step count where all-cause mortality risk levels off — largely a NEAT effect.
- 3–5Creatine monohydrate dose — no loading needed.
- 3–6Pre-training caffeine dose that reliably improves strength and endurance output.
- 25–38Daily fibre intake linked to lower all-cause mortality and a healthier gut microbiome.
- 10–20Hard working sets per muscle per week for hypertrophy.