1. Wall, B.T., Gorissen, S.H., Pennings, B. et al. (2015). "Aging Is Accompanied by a Blunted Muscle Protein Synthetic Response to Protein Ingestion." PLOS ONE. — Demonstrates reduced MPS response to protein in older adults.
2. Katsanos, C.S., Kobayashi, H., Sheffield-Moore, M. et al. (2006). "A high proportion of leucine is required for optimal stimulation of the rate of muscle protein synthesis by essential amino acids in the elderly." American Journal of Physiology-Endocrinology and Metabolism. — Shows older adults need higher leucine concentrations to trigger MPS.
3. Paddon-Jones, D., Sheffield-Moore, M., Zhang, X.J. et al. (2004). "Amino acid ingestion improves muscle protein synthesis in the young and elderly." American Journal of Physiology-Endocrinology and Metabolism. — Demonstrates EAAs effectively stimulate MPS in older populations.
4. Dickinson, J.M., Fry, C.S., Drummond, M.J. et al. (2011). "Mammalian target of rapamycin complex 1 activation is required for the stimulation of human skeletal muscle protein synthesis by essential amino acids." The Journal of Nutrition. — Confirms mTOR activation is essential for EAA-stimulated muscle building.
5. Mitchell, W.K., Williams, J., Atherton, P. et al. (2012). "Sarcopenia, dynapenia, and the impact of advancing age on human skeletal muscle size and strength." Frontiers in Physiology. — Documents the 1-2% per year muscle loss after 40.
6. Ferrando, A.A., Wolfe, R.R., Hirsch, K.R. et al. (2023). "International Society of Sports Nutrition Position Stand: Effects of essential amino acid supplementation on exercise and performance." Journal of the International Society of Sports Nutrition, 20(1). — The ISSN's official position on EAA supplementation, confirming: free-form EAAs stimulate MPS more effectively than equivalent protein; aging requires greater leucine proportion to overcome anabolic resistance; EAA supplementation enhances functional outcomes in anabolic-resistant populations.
7. Jäger, R., Kerksick, C.M., Campbell, B.I. et al. (2017). "International Society of Sports Nutrition Position Stand: protein and exercise." Journal of the International Society of Sports Nutrition. — Establishes protein and amino acid recommendations for athletes.
8. Churchward-Venne, T.A., Breen, L., Di Donato, D.M. et al. (2014). "Leucine supplementation of a low-protein mixed macronutrient beverage enhances myofibrillar protein synthesis in young men." American Journal of Clinical Nutrition. — Demonstrates leucine enrichment enhances MPS.