When it comes to weight management and athletic performance, protein consumption has been one of the most researched areas in the field of nutrition. Some athletes swear by whey protein for muscle building, while vegans rely on soya protein for a high quality, plant based protein source.
Studies have also discovered that although soya and milk proteins are both considered to be high quality, complete sources of amino acids, they appear to have different rates of digestion. This in turn affects how fast their respective amino acids appear in circulation and their ability to stimulate muscle protein building. Soya and dairy proteins also have different amounts of leucine, a branched chained amino acid that serves as a key signal in muscle tissue to stimulate protein synthesis. And studies also suggest that dairy proteins, like casein play an important role in preventing muscle protein breakdown. Findings like these have raised the question by researchers and athletes alike “What is the best source of protein to maximise muscle building?”
Well, an ever-expanding area of research comparing the effects of different protein sources on performance is suggesting a combination of both soya and dairy proteins may in fact be best.
In a one-of-a-kind, double blind, placebo-controlled clinical study, researchers from the University of Texas provided 20 healthy young athletes with either a protein blend (a combination of soya, whey and casein) or whey protein drink immediately after a one-hour bout of high intensity leg resistance exercise. Muscle biopsies were taken at baseline and twice during the post exercise period. What researchers discovered was that muscle protein synthesis rates were stimulated by both protein treatments but to a greater extent by the protein blend. Researchers concluded that the protein blend which provided both fast an slowly digested proteins may have prolonged the delivery of amino acids to muscle tissue thus extending the period of muscle protein synthesis.
From: GNLD Lifestyle Magazine, West Africa (03/14)