Eating about 1.6 grams of protein for every kilogram you weigh each day while lifting weights gives you the biggest muscle and strength gains you can get from protein. Eating more than that doesn't give you any extra benefit.
From This Is Why Your Workouts Stopped Working · videoSee the scientific wording
Consuming protein at a dosage of 1.6 grams per kilogram of body weight per day during a resistance training program produces the maximum possible increases in muscle mass and strength, and additional protein intake beyond this level does not provide further benefits.
Contradicted by evidence
Randomized trials2 good-quality studies contradict this claim.
What the research says
2 studies reviewedSupporting (0)
No supporting studies found yet
We'll keep looking as more research is published.
Contradicting (2)
Randomized Controlled TrialHuman2024
The study gave older women either 0.8 or 1.4 grams of protein per kilogram of body weight while they lifted weights, and both groups gained the same amount of muscle and strength, so eating more protein didn't help—so it doesn't support the idea that more protein (up to 1.6) is better.
Randomized Controlled TrialHuman2023
The study found that people who already eat a lot of protein don't get extra muscle or strength benefits from adding more protein, so the point where extra protein stops helping is probably lower than 1.6 grams per kilogram.
Quality-weighted scoring: we follow the GRADE framework — each study is rated High, Moderate, Low, or Very Low based on study design, methodology rigor, and risk of bias. A single high-quality RCT can outweigh several weaker observational studies.
Scores reflect study quality, not just count.
When you lift weights, your muscles get a signal to build new muscle protein. Eating protein gives the building blocks. But once you have enough, extra protein doesn't add more.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 2 contradicting studies
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Eating about 1.6 grams of protein for every kilogram you weigh each day while lifting weights gives you the biggest muscle and strength gains you can get from protein. Eating more than that doesn't give you any extra benefit.
Mechanism
2 studiesLifting weights makes your muscles build new protein. Eating protein gives the materials. But once you have enough, extra protein doesn't help more.
When you lift weights, your muscles get a signal to build new muscle protein. Eating protein gives the building blocks. But once you have enough, extra protein doesn't add more.
Resistance exercise creates mechanical tension in muscle fibers, which activates a signaling pathway that increases muscle protein synthesis.
Dietary protein provides amino acids, especially leucine, which further stimulate muscle protein synthesis.
The muscle protein synthesis response is saturable; when amino acid levels are already high, additional protein does not further increase synthesis.
Over time, the cumulative muscle protein synthesis leads to muscle growth and strength gains, but only up to the point of saturation.
Evidence from Studies
Last searched 29d ago
Supporting (0)
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Contradicting (2)
Community contributions welcome
The study gave older women either 0.8 or 1.4 grams of protein per kilogram of body weight while they lifted weights, and both groups gained the same amount of muscle and strength, so eating more protein didn't help—so it doesn't support the idea that more protein (up to 1.6) is better.
The study found that people who already eat a lot of protein don't get extra muscle or strength benefits from adding more protein, so the point where extra protein stops helping is probably lower than 1.6 grams per kilogram.
Score Breakdown
No multi-axis breakdown available yet. The overall Pro / Against score above is the best signal.
- No clinical evidence is available; the score reflects mechanistic plausibility only.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
Systematic Review and Meta-Analysis of Randomized Controlled Trials on Protein Intake and Resistance Training for Muscle and Strength Gains
Comprehensive search of RCTs comparing various protein intakes (e.g., 1.2, 1.6, 2.0 g/kg/day) during resistance training, with outcomes of muscle mass and strength, and meta-analysis of dose-response.
Randomized Controlled Trial Comparing 1.6 g/kg/day vs 2.0 g/kg/day Protein on Muscle and Strength Gains in Resistance-Trained Adults
Randomized trial with participants performing resistance training, assigned to protein intake of 1.6 vs 2.0 g/kg/day for 12 weeks, measuring lean mass and strength.
Prospective Cohort Study of Protein Intake and Resistance Training Outcomes in Athletes
Follow a cohort of resistance-trained individuals, record protein intake and training, measure changes in muscle and strength over 6 months.
Cross-Sectional Study of Protein Intake and Muscle Mass in Resistance-Trained Individuals
Survey and measure muscle mass and strength in a group of resistance-trained individuals, correlate with protein intake.