Public Release: 

Turns out protein quality matters when it comes to building muscle

Internationally venerated skeletal muscle scientist takes a critical look at how protein quality impacts muscle mass and strength gains with resistance exercise

Pollock Communications

Rosemont, IL, October 25, 2016 - Attention Crossfit®, HIIT, Orange Theory® and absolutely anyone who cares about maintaining muscle mass - Tier 1 Canada Research Chair in Skeletal Muscle Health, Dr. Stuart M. Phillips of MacMaster University, reasons that the quality of protein you consume for muscle building with resistance training may be more important than you realize. In a recent article in Nutrition and Metabolism, Dr. Phillips reviewed the current science to examine the effects of the quality of supplemental protein on changes in muscle mass, strength and body composition when combined with strength training. His comprehensive inquiry suggests that based on the new proposed method to evaluate protein quality using its indispensable (or essential) amino acid composition and its digestibility, protein sources that provide leucine (an essential amino acid) - such as whey protein - are the strongest determinant of muscle protein synthesis and likely muscle growth.

"My assessment of the data on protein supplementation and resistance exercise reveals that the amount of leucine in a protein supplement has the greatest impact on muscle protein synthesis," said, Dr. Phillips. "Leucine is not only a building block for protein, but a trigger for working muscles to synthesize more protein. In essence, it turns on muscle protein synthesis like a light switch so that over time, there could be greater gains in lean body mass and strength, and subsequently, body composition improvements."

Proteins with the greatest content of leucine include whey protein isolate or concentrate. Whey protein is a milk protein that is considered high-quality due to its amino acid profile and high score for digestibility. Based on the culmination of data inspecting protein types and muscle protein synthesis, whey protein rated higher than other protein sources such as soy, pea or rice.

"The outcome of this review isn't just applicable to strength trainers," Dr. Phillips notes. "As we age, muscle loss becomes prevalent if we don't thwart the decline. Leucine-rich whey protein supplementation, combined with resistance exercise, may be one way to help preserve muscle mass throughout the lifespan."

While more research is warranted to further characterize proteins based on their quality, digestibility and amino acid profile, as well as to identify their impact on the aging population - at this point, consumers should reach for a leucine-containing protein supplement, like whey, to maximize gains from hard workouts.

###

To read the complete review: http://nutritionandmetabolism.biomedcentral.com/articles/10.1186/s12986-016-0124-8

About the Whey Protein Research Consortium

The Whey Protein Research Consortium (WPRC) is an international partnership of dairy cooperatives, associations, processors and multinational companies dedicated to working together to discover and share whey's unique health benefits through scientific evidence since 2003. The WPRC uniquely serves the dairy industry by expanding global usage of whey protein through the research and amplification of its health benefits. The goal of the integrated research efforts is to develop a body of knowledge that establishes measurable whey protein health and wellness benefits, creating a strong foundation for the development of scientific substantiation to support new health, qualified health and structure function claims.

This study was funded and supported by the Canadian Institutes for Health Research, the National Science and Engineering Research Council of Canada, and the Canada Research Chairs program.

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.