Why Muscle Mass and Strength are Important
The goal of retaining lean muscle mass and strength should not be limited to avid gym gurus. While exercise enthusiasts may be motivated by appearance and physique, everyone should be interested in retaining muscle mass as a means of preserving long term health. Research increasingly shows that loss of muscle mass and strength has an adverse impact on health, particularly during aging.
Sarcopenia is the technical term for age-related muscle loss. According to a 2014 review published in "The Lancet: Diabetes & Endocrinology," loss of muscle mass and strength is an important risk factor for accelerating rates of physical disability, hospitalization, and death in the older population, and is associated with the progressive health implications of diabetes, obesity, hyperthyroidism, hypercortisolism, vitamin D deficiency, osteoporosis, rheumatoid arthritis, COPD, congestive heart failure, renal disease and more.
Retaining muscle mass and strength is critical as individuals age. Peak muscle mass and strength is seen between 20 and 30 years of age. Small decreases are noted between ages 30 and 50, and decreases accelerate after the fifth decade of life, with some people experiencing as much as a 15 percent strength loss per decade, with more than 50 percent of fast twitch muscle fibers being lost by 75 years of age.
Glutathione and Muscle Mass
Glutathione isn’t typically a go-to supplement for supporting muscle mass and strength, but according to a randomized, double-blind, placebo-controlled study published in 2018 in the "Journal of the International Society of Sports Nutrition," glutathione may be a key participant in building muscle mass and strength. In this study, 75 resistance-trained males were randomly assigned to ingest 200 mg/day of glutathione + 2 grams/day of L-citrulline (GSH + CIT), 2 grams/day of L-citrulline-malate, or cellulose placebo daily while also participating in 8 weeks of resistance training. Body composition and muscle strength were tested before and after 4 and 8 weeks of resistance training and supplementation. After 4 weeks, lean muscle mass and strength was positively correlated (p < 0.05) and significantly increased in the GSH + CIT group, but not in the L-citrulline-malate or cellulose placebo groups. It is worth emphasizing, though, that this study was conducted in subjects already engaged in regular resistance training (males, ages 18-35, who performed resistance training at least three times weekly for a year), so we cannot necessarily extrapolate the results to individuals who do not participate in this kind of activity.
On the surface, we might question how glutathione can be a muscle-builder since it’s best known for its role as a master antioxidant. Apart from this traditional function, glutathione helps to preserve the muscle protein synthesis pathway. How? Low molecular weight thiols, such glutathione, have been shown to upregulate the nitric oxide (NO) pathway. As it interacts with NO to form S-nitrosoglutathione (GSNO), it stabilizes NO so it is released slowly. Its antioxidant effects also protect NO from oxidative damage, potentiating its effectiveness. NO influences protein kinase B (Akt) signaling though a cGMP/phosphoinositide 3-kinase (PI3K) dependent pathway, which is the primary pathway for upregulating translation initiation required for muscle protein synthesis. Therefore, glutathione preserves NO so it is available for upregulating pathways required for building muscle.
Resistance training is instrumental for building and maintaining lean muscle mass and strength. But this doesn’t mean that all patients need to purchase a gym membership and fall in love with squats and deadlifts. Body weight training, which requires no special equipment, can be effective. Many elderly individuals are prescribed physical therapy programs. Glutathione supplementation may help enhance the intended outcomes of these programs. Not only that, but all individuals in every life stage can engage in strength training routinely to stay mobile and capable of everyday activities and to prevent falls and fractures. Dumbbells and barbells may appeal to certain populations, but resistance bands or a person’s own body weight can be effective for those who prefer not to join a gym or to buy cumbersome equipment.
The role of glutathione can reach beyond its traditional role as an antioxidant. Evidence suggests it can be a helpful adjunct to muscle building protocols, and as a result, potentially reduce the risk for various age-related health issues.