The Claim
In young men undergoing resistance training, supplementing a plant-based diet with soy protein isolate to achieve 1.6 g/kg/day of total protein results in comparable increases in leg lean mass as supplementing an omnivorous diet with whey protein.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
When young men lift weights and consume 1.6 grams of protein per kilogram of body weight daily, adding soy protein isolate to a plant-based diet produces the same increase in leg muscle mass as adding whey protein to an omnivorous diet.
See the scientific wording
In young men undergoing resistance training, supplementing a plant-based diet with soy protein isolate to reach 1.6 g/kg/day of total protein results in comparable increases in leg lean mass as supplementing an omnivorous diet with whey protein, indicating that soy protein can effectively support muscle accretion when intake is sufficient.
When a person consumes 1.6 grams of protein per kilogram of body weight from soy or whey, the amino acid leucine from either source triggers a molecular signal in muscle cells that turns on protein building. This signal increases the production of muscle fibers, causing them to grow larger over time when combined with resistance training, resulting in more leg muscle mass.
What the research says
1 studyWhen young men lifted weights and got 1.6 grams of protein per kilogram of body weight, those who got it from soy gained just as much leg muscle as those who got it from whey — so soy works just as well for building muscle when you get enough protein.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.