Skeletal muscle is an extremely important body tissue, which plays an integral role in strength, exercise and sporting performance. Our muscle mass is also critically linked to healthy metabolic control, as it the primary site of glucose disposal and fat metabolism, and robust physical function as we age.
The role of maintaining muscle mass during weight loss and as we age is a topic that has received increasing attention over the last several years due to the muscle wasting that occurs during energy deprivation (weight loss) and the aging process. Optimizing our muscle mass, then, has enormous implications for preventing chronic disease, functional capacity, and quality of life.
Research has shown that higher protein diets (1) promote gains in muscle mass, especially when resistance training is also performed; (2) rescue muscle mass loss during energy restriction for weight loss; and (3) reduce the natural reduction of muscle mass that occurs during aging.
In this context, it is not just a matter of how much protein we consume, but also the protein quality when considering how to optimize gaining and maintaining muscle mass. Protein quality is a function of protein digestibility, amino acid composition, and the resulting amino acid availability to support metabolic function and muscle tissue remodeling.
Whey protein is regarded as one of the highest-quality proteins, due to its rapid digestibility and unique amino acid content, which is high in both essential amino acids and branched-chain amino acids (especially leucine). These amino acids are believed to be of critical importance in the muscle tissue growth and repair pathways.
Consuming whey protein has a robust ability to stimulate muscle protein synthesis and initiate muscle tissue remodeling. Research has demonstrated that whey protein stimulates muscle protein synthesis to a greater degree than other dairy proteins, such as casein, and plants proteins, such as soy or pea. This is primarily due to the high amino acid leucine content and the complete amino acid composition of whey.
Drinking up to 60g of actual weight whey protein around the time that resistance training is performed is an ideal way to support muscle mass for optimal healthy aging and physical function.