Every week our coaches at Peak Fitness in Orem read the actual studies behind a popular training or nutrition claim and boil them down to what holds up and what to do with it. Here's No. 04.
The evidence
- The daily number: across 49 randomized trials (1,863 people), extra protein boosted muscle gains from training, but for most people there was no clear extra benefit beyond about 0.7 g per lb a day. The upper range was about 1 g per lb.
- Protein is the amplifier, not the engine: training alone added about 2.4 lb of lean mass over about 13 weeks. Extra protein added about two-thirds of a pound on top.
- The anabolic window: in a meta-analysis of 23 trials, timing protein around your workout made no real difference once total daily protein was accounted for. Total intake was the strongest predictor of growth.
- The "30 g per meal" limit: in a 2023 trial, 100 g of protein after lifting kept building muscle protein for over 12 hours, more than 25 g did.
The protocol
- →Aim for 0.7 g per lb of body weight a day. Want every edge? Go up to 1 g per lb.
- →Split it across 4 or more meals, about 0.18 g per lb each (about 33 g for a 180 lb person).
- →Missed your post-workout shake? You're fine. Hit the daily total.
Honest caveat
The 100 g study was one small trial in 36 young men, measured over a single day. It shows bigger meals aren't wasted, not that one giant meal beats spreading it out.
Not medical advice. Kidney disease or on a protein-restricted diet? Talk to your doctor before you increase protein.
Sources
- Morton 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. Br J Sports Med, 2018
- Schoenfeld & Aragon. How much protein can the body use in a single meal for muscle-building? J Int Soc Sports Nutr, 2018
- Schoenfeld, Aragon & Krieger. The effect of protein timing on muscle strength and hypertrophy: a meta-analysis. J Int Soc Sports Nutr, 2013
- Trommelen et al. The anabolic response to protein ingestion during recovery from exercise has no upper limit in magnitude and duration. Cell Rep Med, 2023