Study: Soy Protein Blend Promotes Muscle Growth

ST. LOUISA study published inThe Journal of Nutrition found soy and dairy protein blend promoted muscle protein synthesis after exercise (J. Nutr. March 1, 2013 jn.112.168021). In the double blind, randomized clinical trial, researchers at the University of Texas compared a soy/dairy protein blend (using SUPRO from DuPont Nutrition & Health).  with whey protein, testing for fractional synthetic rate and branch-chain amino acid (BCAA) concentrations.

Researchers collected muscle biopsies of the 19 participants at rest, then at two intervals after resistance exercise and ingestion. The whey protein group experienced an earlier amplitude of blood BCAA, while the blend group's BCAA levels remained elevated later into the recovery period. The protein blend subjects also caused an elevated fractional synthetic rate for a longer time compared to the whey protein.

Sources of high-quality protein contain all the essential amino acids and have individual characteristics thought to offer a unique advantage for muscle growth," said Blake Rasmussen, Ph.D., interim chair, Dupont department of nutrition and metabolism and principle investigator of the study.  This is the first study to test the effects of combining soy with the dairy proteins, whey and casein, for promotion of lean body mass gain."

Increasingly, scientists are researching the benefits of soy protein. In October, a PLOS One study suggested soy protein reduces body and liver fat. For more information on protein applications in the natural products industry, visit INSIDER's Protein Topic Feed.