Soy- Dairy Combo Post Exercise Helps Build Muscle Mass, Researchers Say

Drinking a blend of soy and dairy proteins after resistance exercise could help build muscle mass, a team of researchers has found.

The study, conducted by researchers at University of Texas Medical Branch, found that a combination of soy, casein and whey prolong delivery of amino acids to the muscles.

"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.

Previous research from the UTMB had shown that a combo of soy and dairy was better than soy alone in helping the body build muscle mass. The new study is an extension of that research.

"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, according to a news release. "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 was a double-blind, randomized clinical trial that included 16 people between ages 19 and 30 years. Researchers wanted to know whether or not consumption of dairy-soy post exercise would prolong amino acid delivery to the muscles.

The participants were given a soy-dairy blend or a single protein source (whey protein isolate), according to a news release.

Researchers took muscle samples before and after exercise. Participants consumed the drinks one hour after work-out.

The team found that soy-dairy blend increases amino acid levels around the muscles, helping them to build more mass. The study also showed that there was less protein breakdown when participants drank the blend rather than just the whey protein.

The study is published in the Journal of Applied Physiology.