The Claim

Untrained young adults who consume approximately 1.3 g/kg/day of dietary protein and supplement with additional leucine-matched soy or whey protein, resulting in a total intake of ~1.6–1.8 g/kg/day, while engaging in resistance training three times per week for 12 weeks, experience significant improvements in lean body mass and strength, indicating that protein supplementation supports training adaptations in individuals whose baseline protein intake is below the 1.62 g/kg/day threshold for maximal benefit.

Source: No Significant Differences in Muscle Growth and Strength Development When Consuming Soy and Whey Protein Supplements Matched for Leucine Following a 12 Week Resistance Training Program in Men and Women: A Randomized Trial

What the research says

Supports is higher

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

Supports
74score
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

If young adults who aren't used to working out eat a bit more protein—especially from whey or soy—and lift weights 3 times a week for 3 months, they’ll likely gain more muscle and get stronger, even if they weren’t eating enough protein to start with.

See the scientific wording

Untrained young adults consuming approximately 1.3 g/kg/day of dietary protein from food and supplementing with additional leucine-matched soy or whey protein (total ~1.6–1.8 g/kg/day) while performing resistance training 3 times per week for 12 weeks experience significant improvements in lean body mass and strength, suggesting that protein supplementation supports training adaptations in individuals below the 1.62 g/kg/day threshold for maximal benefit.

What the research says

1 study
  1. Study: No Significant Differences in Muscle Growth and Strength Development When Consuming Soy and Whey Protein Supplements Matched for Leucine Following a 12 Week Resistance Training Program in Men and Women: A Randomized Trial

    The study shows that adding protein supplements to a regular diet while lifting weights helps young, untrained people gain muscle and get stronger, whether they use soy or whey protein.

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

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