The Claim

A daily protein intake of 1.4 g/kg body mass from whey or soy protein during 9 months of resistance training results in greater increases in lean body mass compared to a daily intake of 1.1 g/kg from carbohydrate.

Source: Whey Protein Supplementation During Resistance Training Augments Lean Body Mass

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
48score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Cause and effect
1 study reviewed
In plain English

People who consume 1.4 grams of protein per kilogram of body weight daily from whey or soy while doing resistance training for 9 months gain more lean body mass than those who consume 1.1 grams per kilogram from carbohydrate.

See the scientific wording

Daily protein intake of 1.4 g/kg body mass from whey or soy protein during 9 months of resistance training leads to greater lean body mass gains than a daily intake of 1.1 g/kg from carbohydrate, indicating that total protein intake above 1.1 g/kg may be necessary for optimal muscle adaptation.

Why this might work

When a person consumes whey protein after training, the body quickly absorbs a large amount of leucine, which turns on a key growth signal in muscle cells. This signal tells the cells to build more proteins, leading to thicker muscle fibers and more lean body mass over time. Higher daily protein intake ensures this signal stays active long enough to support continuous muscle growth.

Verified mechanismbased on 1 study

What the research says

1 study

  1. Study: Whey Protein Supplementation During Resistance Training Augments Lean Body Mass

    The study compared groups with different total protein intakes (1.1 vs. 1.4 g/kg) and found significantly greater lean mass gains in the higher protein groups. This supports a causal relationship between total protein intake above 1.1 g/kg and enhanced muscle adaptation during resistance training.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.