Soy and dairy protein blend may be beneficial for building muscle mass

Consuming a blend of soy and dairy proteins after resistance exercise may have additional benefits for building muscle mass, a recent study from the University of Texas Medical Branch (UTMB) says. The study published online in the Journal of Applied Physiology has found that using a protein blend of soy, casein and whey post-workout prolongs the delivery of select amino acids to the muscle for an hour longer than using whey alone. It also shows a prolonged increase in amino acid net balance across the leg muscle during early post-exercise recovery, suggesting prolonged muscle building.

The study was conducted by researchers from UTMB in collaboration with DuPont Nutrition and Health. “This study sheds new light on how unique combinations of proteins, as opposed to single protein sources, are important for muscle recovery following exercise and help extend amino acid availability, further promoting muscle growth,” said Blake B. Rasmussen, chairman of UTMB’s Department of Nutrition and Metabolism and lead researcher of the study.

This new research, using state-of-the-art methodology, builds on an earlier publication reporting that a soy-dairy blend extends muscle protein synthesis when compared to whey alone, as only the blended protein kept synthesis rates elevated three to five hours after exercise. Together, these studies indicate that the use of soy-dairy blends can be an effective strategy for active individuals seeking products to support muscle health.

“Because of the increased demand for high-quality protein, this study provides critical insight for the food industry as a whole, and the sports nutrition market in particular,” said Greg Paul, global marketing director for DuPont Nutrition and Health. “With more and more consumers recognizing the importance of protein for their overall health and well-being, the results of this study have particular relevance to a large segment of the population, from the serious sports and fitness enthusiast to the mainstream consumer.”

The study demonstrates that consuming a soy-dairy blend leads to a steady rise in amino acids, the building blocks of muscle. The data showed that the soy-dairy blend yields an increase in select amino acid delivery for about an hour longer than the use of whey protein alone. The blend also sustained a greater positive net amino acid balance than whey, suggesting there is less muscle protein breakdown during the time period shortly after consumption of a blended protein product.