The Study
Soy-dairy protein blend and whey protein ingestion after resistance exercise increases amino acid transport and transporter expression in human skeletal muscle.
This study gave two groups of young people different protein drinks after working out and measured what happened in their muscles. It found one drink kept amino acids in the muscle a little longer, but both drinks helped muscles build protein the same amount. So it shows a small difference in timing, not a big difference in results.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
After working out, your muscles need protein to repair. This study tested if mixing different proteins (soy, casein, whey) helps your muscles hold onto amino acids longer than just drinking whey.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 568 / 100
Quality score
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes — this means the blend helps your muscles retain amino acids longer, which could support recovery over time, even if it doesn't make you build muscle faster right away.
- 2After drinking the protein mix, your muscles kept a positive amino acid balance for up to 2 hours — 6.8 more units per 100g of leg muscle at 60 and 120 minutes — but built muscle at the same rate as whey.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Journal of applied physiology
Year
2014
Authors
P. Reidy, D. Walker, J. Dickinson, D. Gundermann, M. Drummond, K. Timmerman, Mark B. Cope, R. Mukherjea, K. Jennings, E. Volpi, B. Rasmussen
Related Content
Claims (5)
Consuming a blend of soy and dairy proteins leads to a longer-lasting increase in amino acids in the blood compared to consuming whey protein alone, because the proteins digest at different rates and maintain amino acid levels for a longer time.
After resistance exercise, young adult men who consume a soy-dairy protein blend maintain a higher net amino acid balance in their leg muscles at 60 and 120 minutes compared to those who consume whey protein, even though both protein blends stimulate muscle protein synthesis to the same extent.
After exercise, young adult men who consume either a soy-dairy protein blend or whey protein with equal leucine levels experience the same increase in muscle protein synthesis.
After resistance exercise, consuming either a soy-dairy protein blend or whey protein results in the same increase in the activity of five specific genes involved in amino acid transport in human muscle cells.
After resistance exercise, both a soy-dairy blend and whey protein increase the same amino acid transporter protein to the same degree, but only the soy-dairy blend briefly increases a specific regulatory protein in the cell nucleus, showing different early signaling pathways lead to the same outcome.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.