Cysteine-Rich Whey Protein Beats Casein for Strength Gains

Cysteine-Rich Whey Protein Beats Casein for Strength Gains

Whey protein is the best source of protein to support lean muscle and also lose fat. A number of preclinical studies conducted in rodents have shown that whey protein might possess some anti-cancer and ant-inflammatory properties. Other studies have shown that the protein might have an effect on muscle growth, though this observation is debatable. Whey protein is often made up of beta-lactoglobulin (65%), alpha-lactalbumin (25%), bovine serum albumin (8%), and immunoglobulins. Whey protein provides cysteine, which is critical in the biosynthesis of glutathione. The health benefits of whey protein are attributed to the fact that whey protein can increases glutathione levels.

There is currently a great deal of hype about glutathione supplementation, highly popularized as a “miracle” means to boost health, prevent disease and fight aging. The main function of glutathione is to protect your cells and mitochondria from oxidative and peroxidative damage. As you age, your body’s ability to produce glutathione decreases. Glutathione has been established as one of the most important intracellular antioxidant.

Bursting onto the health scene as “the master antioxidant,” glutathione has been in the spotlight recently for its ability to enhance the immune system and increase energy. Glutathione is a substance found in every cell in the body, where it acts as an antioxidant to neutralize free radicals and prevent cellular damage. Chemically, glutathione is a simple molecule composed of three protein building blocks or amino acids- cysteine, glutamine and glycine.

Researchers examined the effect of a cysteine-rich whey protein isolate supplementation in combination with resistance training on muscle strength and lean body mass (LBM) in elderly individuals. They hypothesized that the cysteine-rich whey protein group would experience a greater increase in muscle strength and lean body mass versus the control group (casein). Participants were randomly assigned into two groups. The experimental group received a cysteine-rich whey protein isolate (20 g/day) and the control group received casein (20 g/day) during a 135-day period. In addition, both groups performed the same resistance training program (3 times per week). Body composition (DXA) and muscle strength (leg press) were measured. Results in this selected group show an increase in all three muscle strength variables (absolute, normalized by BW and by LBM) by 31.0 %, 30.9 % and 30.0 %, respectively in the casein group as well as 39.3 %, 39.9 % and 43.3 %, respectively in the whey protein isolate group after the intervention. The increases in muscle strength favored whey protein isolate versus casein by approximately 10 % when expressed in kg per kg of bodyweight and in kg per kg lean body mass. No significant changes were found between pre-and-post intervention in both groups for total lean muscle. The researchers showed increases in muscle strength in both groups after resistance training, however, significant additional increases were observed in muscle strength with the addition of a cysteine-rich whey protein isolate versus casein.

Be sure to check out Infinite Labs Whey Protein Isolate Section

Karelis AD, et al. Effect of cysteine-rich whey protein (Immunocal®) supplementation in combination with resistance training on muscle strength and lean body mass in non-frail elderly subjects: A randomized, double-blind controlled study. J Nutr Health Aging. 2015;19(5):531-536.