How supplementing with L-glutamine and L-leucine will support your heavy training load.

While the immune-strengthening benefits of acute (less than 60 minutes) vigorous training are widely known, several studies have discovered the temporary immune-suppressing effects of longer duration high intensity exercise. According to these studies, athletes who had undergone long, heavy training episodes saw suppressed immune function for several hours to days. As Nieman et al. summarizes, “the best evidence supports that high exercise training workloads, competition events, and the associated physiological, metabolic, and psychological stress are linked to immune dysfunction, inflammation, oxidative stress, and muscle damage.” 

The effects of these heavy training episodes were particularly pronounced in runners, cyclists, and triathletes, though the theme persists across other types of exercise and competition. Revitalizing your immune system after intense exercise starts with proper sleep hygiene, hydration, and food intake, but another important pathway has gained recognition in recent years: L-glutamine supplementation. 

L-glutamine is the most abundant amino acid in the bloodstream and plays several important roles in cellular regulation throughout the body. Among other functions, L-glutamine is a key component of muscle recovery, gut health, and immune support. Given its prevalence in the body, L-glutamine is considered conditionally essential, meaning the average person with limited exercise can get enough from diet alone. In people who exercise more frequently and at a higher intensity, L-glutamine levels are often insufficient from diet alone. For these individuals, L-glutamine supplementation becomes necessary. 

For athletes of this class, further studies have shown that L-glutamine supplementation promotes muscle tissue repair, faster recovery of peak force, and improved immune function after heavy training episodes. Magnitude of strength loss after exercise was significantly limited with L-glutamine ingestion. Further, combining L-glutamine with L-leucine (a main component of BCAAs) results in a greater rate of recovery in response to muscle-damaging exercise. The long-term effects of glutamine and leucine, when taken in combination, have included moderate to large strength gains over placebo. For a look at the nitty gritty details, here is one great study on why glutamine supplementation should be a mainstay recovery tool for your heavy load training. 

Fortunately, our stack contains the optimal dose of glutamine, leucine, and 4 other ingredients to support your recovery and growth. 


  • Legault, Zachary. Nicholas Bagnall, Derek S. Kimmerly. The Influence of Oral L-Glutamine Supplementation on Muscle Strength Recovery and Soreness Following Unilateral Knee Extension Eccentric Exercise. International Journal of Sports Nutrition & Exercise Metabolism. 2015. 
  • Waldron, Mark. The effects of acute leucine or leucine-glutamine co-ingestion on recovery from eccentrically biased exercise. Amino Acids. 2018. 
  • Boelens, Petra G. Glutamine Alimentation in Catabolic State. The Journal of Nutrition. 2001.
  • Norton, Layne E. Leucine Regulates Translation Initiation of Protein Synthesis in Skeletal Muscle after Exercise. Branched-Chain Amino Acids in Exercise. Journal of Nutrition. 
  • Shimomura, Yoshiharu. Nutraceutical Effects of Branched-Chain Amino Acids on Skeletal Muscle. The Journal of Nutrition. 2006. 
  • Blomstrand, Eva. A Role for Branched-Chain Amino Acids in Reducing Central Fatigue. The Journal of Nutrition. 2006. 
  • Nieman, David C., Laurel M. Wentz. The compelling link between physical activity and the body’s defense system. Journal of Sport and Health Science. 2019. 
  • Song QH, Xu RM, Zhang QH, Shen GQ, Ma M, Zhao XP, Guo YH, Wang Y. Glutamine supplementation and immune function during heavy load training. International Journal of Clinical Pharmacology and Therapeutics. 2015.