The Claim

In untrained young adults, twelve weeks of supervised resistance training performed three times per week results in an average increase of 1.54 kg in lean body mass and 0.68 kg in total body mass, with significant improvements in leg extensor and flexor strength, irrespective of whether protein supplementation is derived from soy or whey, provided leucine intake is matched at 2 grams per day.

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 do strength training 3 times a week for 12 weeks, they’ll gain about 1.5 kg of muscle and get stronger legs — and it doesn’t matter if their protein shake is made from soy or whey, as long as both have the same amount of leucine (2 grams per day).

See the scientific wording

Twelve weeks of supervised resistance training 3 times per week in untrained young adults leads to an average increase of 1.54 kg in lean body mass and 0.68 kg in total body mass, with significant gains in leg extensor and flexor strength, regardless of whether protein supplementation comes from soy or whey when leucine is matched at 2 grams per day.

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 found that young adults gained similar muscle and strength whether they took soy or whey protein, as long as both had the same amount of leucine, which matches what the claim says.

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

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