Macro partitioning
Soy protein supplementation supports muscle growth and strength development comparably to whey protein when both are matched for leucine content during resistance training.
If you are using soy protein to build muscle, ensure your supplement provides about 2-3 grams of leucine per serving (which may require slightly more total soy powder than whey). When matched for this key amino acid, soy supports muscle growth and strength gains just as effectively as whey during resistance training.
These data indicate that increases in lean mass and strength in untrained participants are comparable when strength training and supplementing with soy or whey matched for leucine.
Why this rating
Randomized controlled trial with double-blinding and matched leucine, though limited to untrained individuals.
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
Heidi Lynch et al. · International Journal of Environmental Research and Public Health · 2020
DOI 10.3390/ijerph17113871
Related findings · Macro partitioning
- Total daily protein intake of 1.6 g/kg/day is sufficient for maximizing resistance training-induced muscle gains, with an upper confidence interval of 2.2 g/kg/day.Strong
- Resistance exercise training combined with sufficient dietary protein intake acts synergistically to maximize skeletal muscle hypertrophy, with protein intake saturating around 1.6 g/kg/day for general populations and potentially requiring 2.0-2.2 g/kg/day for resistance-trained individuals.Strong
- Trans fats should be completely eliminated from the diet, as they increase LDL cholesterol, decrease HDL cholesterol, and are directly associated with increased coronary risk.Strong
This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →