Branched Chain Amino Acids (BCAA) have gained immense popularity as dietary supplements among athletes, bodybuilders, and fitness enthusiasts. The concept that BCAAs may have a unique capacity to stimulate muscle protein synthesis has been put forward for more than 35 years1Wolfe RR. Branched-chain amino acids and muscle protein synthesis in humans: myth or reality?. J Int Soc Sports Nutr. 2017;14:30. Published 2017 Aug 22. doi:10.1186/s12970-017-0184-9.
The BCAA types consist of the three essential amino acids L-Leucine, L-Isoleucine, and L-Valine. In most cases, the research on BCAAs has incorporated the combined use of these amino acids, although some research supports using L-leucine alone for muscle health.
The popularity of BCAA is reflected in the fact that its market size was valued at $1.45 billion in 2022. It is estimated to grow at over 5.8% CAGR from 2023 to 20322Branched Chain Amino Acids (BCAAs) Market Size Global Market Insights. Retrieved August 8, 2024 from https://www.gminsights.com/industry-analysis/branched-chain-amino-acids-market#:~:text=Branched%20Chain%20Amino%20Acids%20Market%20size%20was%20valued%20at%20USD,CAGR%20from%202023%20to%202032..
Investing the time to educate yourselves on the various health benefits BCAAs provide can help you create a best-in-class formula that can then be manufactured by a qualified contract development and manufacturing company like Vitaquest. Let’s start by defining what a BCAA supplement is and answering one of the common questions we hear from consumers and new supplement business owners.
What is a BCAA Supplement?
One of the most common questions consumers and new dietary supplement business owners ask is – Do BCAAs work?
Numerous studies have been conducted and published demonstrating BCAA benefits and effectiveness. They are building blocks for all life forms. These amino acids and the metabolites produced from them act as signaling molecules to help activate important functions ranging from protein synthesis to insulin secretion.3Neinast M, Murashige D, Arany Z. Branched Chain Amino Acids. Annu Rev Physiol. 2019;81:139-164. doi:10.1146/annurev-physiol-020518-114455
Research also suggests that BCAAs promote recovery from high-intensity exercise and improve cognition, focus, and psychomotor function4Raizel R, Coqueiro AY, Bonvini A, Tirapegui J. 1 - Sports and Energy Drinks: Aspects to Consider. In Sports and Energy Drinks. Volume 10: The Science of Beverages. Woodhead Publishing; 2019:1-37.. Research has also demonstrated that supplementation with BCAA significantly reduced the breakdown of skeletal muscle in normal and exercising volunteers, 5Louard RJ, Barrett EJ, Gelfand RA.Overnight branched-chain amino acid infusion causes sustained suppression of muscle proteolysis. Metabolism 1995;44(4):424-9. 6MacLean DA, Graham TE, Saltin B. Branched-chain amino acids augment ammonia metabolism while attenuating protein breakdown during exercise. Am J Physiol 1994;267:E1010-22. 7Greer BK, Woodard JL, White JP, Arguello EM, Haymes EM. Branched-chain amino acid supplementation and indicators of muscle damage after endurance exercise. Int J Sport Nutr Exerc Metab 2007;17(6):595-607. 8Coombes JS, McNaughton LR. Effects of branched-chain amino acid supplementation on serum creatine kinase and lactate dehydrogenase after prolonged exercise. J Sports Med Phys Fitness 2000;40(3):240-6. 9Shimomura Y, Murakami T, Nakai N, Nagasaki M, Harris RA. Exercise promotes BCAA catabolism: effects of BCAA supplementation on skeletal muscle during exercise. J Nutr 2004 Jun;134(6 Suppl):1583S-1587S. 10Tang FC. Influence of branched-chain amino acid supplementation on urinary protein metabolite concentrations after swimming. J Am Coll Nutr 2006;25(3):188-94. decreased muscle soreness and muscle fatigue occurring for a few days after exercise, 11Shimomura Y, Murakami T, Nakai N, Nagasaki M, Harris RA. Exercise promotes BCAA catabolism: effects of BCAA supplementation on skeletal muscle during exercise. J Nutr 2004 Jun;134(6 Suppl):1583S-1587S. 12Shimomura Y, Yamamoto Y, Bajotto G, Sato J, Murakami T, Shimomura N, Kobayashi H, Mawatari K. Nutraceutical effects of branched-chain amino acids on skeletal muscle. J Nutr 2006;136(2):529S-532S. and decreased lactic acid levels during exercise.13MacLean DA, Graham TE, Saltin B. Stimulation of muscle ammonia production during exercise following branched-chain amino acid supplementation in humans. J Physiol 1996;493(Pt 3):909-22. 14De Palo EF, Gatti R, Cappellin E, Schiraldi C, De Palo CB, Spinella P. Plasma lactate, GH and GH-binding protein levels in exercise following BCAA supplementation in athletes. Amino Acids 2001;20(1):1-11. 15Coombes JS, McNaughton LR. Effects of branched-chain amino acid supplementation on serum creatine kinase and lactate dehydrogenase after prolonged exercise. J Sports Med Phys Fitness 2000;40(3):240-6. 16Koba T, Hamada K, Sakurai M, Matsumoto K, Hayase H, Imaizumi K, Tsujimoto H, Mitsuzono R. Branched-chain amino acids supplementation attenuates the accumulation of blood lactate dehydrogenase during distance running. J Sports Med Phys Fitness 2007;47(3):316-22.
It’s important to clarify that, although BCAAs are found in varying amounts in proteins, they are not the same as protein and should not be used as a substitute. Instead, they consist of the three specific amino acids already covered in this article that are part of the full amino acid profile found in complete proteins. Likewise, BCAA does not perform the same roles as creatine which is made up of the amino acids arginine, glycine, and methionine. Nevertheless, BCAA can be used as part of a comprehensive program for muscle growth that includes protein and creatine.
Essential Amino Acids and Their Role in BCAA Supplements
Essential amino acids are those that cannot be synthesized by human or other mammalian cells and must be obtained from food or supplements.
The nine essential amino acids include the BCAAs leucine, isoleucine, and valine, histidine, lysine, methionine, phenylalanine, threonine and tryptophan.17Lopez MJ, Mohiuddin SS. Biochemistry, Essential Amino Acids. [Updated 2024 Apr 30]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK557845/ Research has shown that when these essential amino acids are used together with arginine (a conditionally essential amino acid; see below section on conditionally essential amino acids), they were able to stimulate muscle protein synthesis in both young and elderly adults18Volpi E, Mittendorfer B, Wolf SE, Wolfe RR. Oral amino acids stimulate muscle protein anabolism in the elderly despite higher first-pass splanchnic extraction. Am J Physiol. 1999 Sep;277(3 Pt 1):E513-20. 19Paddon-Jones D, Sheffield-Moore M, Zhang XJ, Volpi E, Wolf SE, Aarsland A, Ferrando AA, Wolfe RR. Amino acid ingestion improves muscle protein synthesis in the young and elderly. Am J Physiol Endocrinol Metab. 2004 Mar;286(3):E321-8. 20Paddon-Jones D, Sheffield-Moore M, Zhang XJ, Volpi E, Wolf SE, Aarsland A, Ferrando AA, Wolfe RR. Amino acid ingestion improves muscle protein synthesis in the young and elderly. Am J Physiol Endocrinol Metab. 2004 Mar;286(3):E321-8., and do so more effectively than whey protein supplementation in healthy elderly individuals21Paddon-Jones D, Sheffield-Moore M, Katsanos CS, Zhang XJ, Wolfe RR. Differential stimulation of muscle protein synthesis in elderly humans following isocaloric ingestion of amino acids or whey protein. Exp Gerontol. 2006 Feb;41(2):215-9..
Research22Hirsch KR, Greenwalt CE, Saylor HE, Gould LM, Harrison CH, Brewer GJ, Blue MNM, Ferrando AA, Huffman KM, Mayer-Davis EJ, Ryan ED, Smith-Ryan AE. High-intensity interval training and essential amino acid supplementation: Effects on muscle characteristics and whole-body protein turnover. Physiol Rep. 2021 Jan;9(1):e14655. has also shown that this combination of amino acids enhanced muscular adaptation via increases in protein turnover, supporting greater improvements in muscular size and quality. Likewise, research23Khemtong C, Kuo CH, Chen CY, Jaime SJ, Condello G. Does Branched-Chain Amino Acids (BCAAs) Supplementation Attenuate Muscle Damage Markers and Soreness after Resistance Exercise in Trained Males? A Meta-Analysis of Randomized Controlled Trials. Nutrients. 2021;13(6):1880. Published 2021 May 31. doi:10.3390/nu13061880. also shows that supplementation with BCAAs can reduce muscle damage and ameliorate muscle soreness after resistance exercise in trained males. Additionally, research suggests that BCAAs benefit weight loss. One study24Novin ZS, Ghavamzadeh S, Mehdizadeh A. The Weight Loss Effects of Branched Chain Amino Acids and Vitamin B6: A Randomized Controlled Trial on Obese and Overweight Women. Int J Vitam Nutr Res. 2018;88(1-2):80-89. doi:10.1024/0300-9831/a000511 found that supplementation with BCAAs and vitamin B6 helped reduce waist-to-hip ratio, which may be a function of helping the body maintain lean muscle mass while burning fat.
The Three Primary BCAAs:
While Leucine, Isoleucine, and Valine are collectively known for their muscle health benefits, each amino acid also offers distinct individual advantages.
Leucine
Leucine is the most well-known and prevalent of the three BCAAs. In animal research25Lim CH, Gil JH, Quan H, Viet DH, Kim CK. Effect of 8-week leucine supplementation and resistance exercise training on muscle hypertrophy and satellite cell activation in rats. Physiol Rep. 2018;6(12):e13725. doi:10.14814/phy2.13725, supplementation accompanied by regular exercise training increased the activity of skeletal muscles and improved muscle quality. In human research26Ispoglou T, White H, Preston T, McElhone S, McKenna J, Hind K. Double-blind, placebo-controlled pilot trial of L-Leucine-enriched amino-acid mixtures on body composition and physical performance in men and women aged 65-75 years. Eur J Clin Nutr. 2016;70(2):182-188. doi:10.1038/ejcn.2015.91, when EAA was supplemented along with 20% or 40% leucine, there was a significant improvement in lean mass (i.e., muscle). Additional human research27Pathak K, Zhao Y, Calton EK, et al. The impact of leucine supplementation on body composition and glucose tolerance following energy restriction: an 8-week RCT in adults at risk of the metabolic syndrome. Eur J Clin Nutr. 2024;78(2):155-162. doi:10.1038/s41430-023-01360-1 showed that leucine supplementation during caloric restriction resulted in a greater preservation of muscle mass.
Isoleucine
Isoleucine plays a critical role in various physiological functions, including growth, immunity, protein metabolism, fatty acid metabolism, and glucose transportation. Isoleucine can promote a healthy functioning immune system, including immune organs, cells, and reactive substances. Recent studies have also shown that isoleucine may induce the expression of host defense peptides (i.e., β-defensins) that regulate host innate and adaptive immunity.28Gu C, Mao X, Chen D, Yu B, Yang Q. Isoleucine Plays an Important Role for Maintaining Immune Function. Curr Protein Pept Sci. 2019;20(7):644-651. doi:10.2174/1389203720666190305163135 Isoleucine is also the oxygen-carrying pigment inside of red blood cells and helps to make hemoglobin29Isoleucine. Healthy Encyclopedia. University of Rochester Medical Center. Retrieved August 8, 2024 from https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=19&contentid=Isoleucine..
Valine
Research30Sharma S, Zhang X, Azhar G, et al. Valine improves mitochondrial function and protects against oxidative stress. Biosci Biotechnol Biochem. 2024;88(2):168-176. doi:10.1093/bbb/zbad169 has demonstrated that valine increased the expression of genes involved in mitochondrial biogenesis and dynamics. So, what exactly does this mean? Mitochondria are the parts of our cells that make energy (ATP). The more mitochondria you have, the more energy you can make. “Mitochondrial biogenesis” is a term that means making new mitochondria! Also, the same research showed that Valine reduced oxidative stress in the mitochondria, and improved ATP production.
Non-Essential Amino Acids in BCAAs
Are you wondering what are non-essential amino acids? If so, the term doesn’t mean that these amino acids aren’t important or that the body doesn’t need them. Rather, the term is used to describe amino acids that are not primarily derived from the diet but are synthesized by the body.31Lopez MJ, Mohiuddin SS. Biochemistry, Essential Amino Acids. [Updated 2024 Apr 30]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK557845/
Now that you know the non-essential amino acids definition, here is a list of the specific non-essential amino acids: arginine, alanine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, proline, serine, and tyrosine32Amino acids. MedlinePlus, National Library of Medicine. Reviewed January 19, 2023. Retrieved August 8, 2024 from https://medlineplus.gov/ency/article/002222.htm#:~:text=Nonessential%20means%20that%20our%20bodies,proline%2C%20serine%2C%20and%20tyrosine.—although arginine is also a conditionally essential amino acid (see below section on conditionally essential amino acids).
- Arginine – A precursor to nitric oxide, a vasodilator produced by the body to facilitate circulation.33Tapiero H, Mathe G, Couvreur P, et al. I. Arginine. Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie (France) 2002; 56(9):439-45.
- Alanine – A source of energy for muscles and the central nervous system.34Alanine. Health Encyclopedia. University of Rochester Medical Center. Retrieved August 8, 2024 from https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=19&contentid=Alanine#:~:text=Alanine%20is%20an%20amino%20acid,and%20the%20central%20nervous%20system.
- Asparagine – Helps to break down toxic ammonia within cells.35ASNS gene. MedlinePlus, National Library of Medicine. Retrieved August 8, 2024 from https://medlineplus.gov/genetics/gene/asns/#:~:text=Asparagine%20is%20needed%20to%20produce,the%20brain%20(a%20neurotransmitter).
- Aspartic acid – Functions in the nervous and reproductive systems.36Ota N, Shi T, Sweedler JV. D-Aspartate acts as a signaling molecule in nervous and neuroendocrine systems. Amino Acids 2012;43:1873-86.
- Cysteine – Demonstrated antioxidant effects.37Clemente Plaza N, Reig García-Galbis M, Martínez-Espinosa RM. Effects of the usage of l-cysteine (l-Cys) on human health. Molecules 2018;23(3):575.
- Glutamic acid/glutamine – Required by the immune system, gastrointestinal tract, kidneys, and liver.38Shabert JK, Winslow C, Lacey JM, Wilmore DW. Glutamine-antioxidant supplementation increases body cell mass in AIDS patients with weight loss: a randomized, double-blind controlled trial. Nutrition 1999;15:860-4.
- Glycine – Acts as a neurotransmitter in the central nervous system.39Razak MA, Begum PS, Viswanath B, Rajagopal S. Multifarious Beneficial Effect of Nonessential Amino Acid, Glycine: A Review [published correction appears in Oxid Med Cell Longev. 2022 Feb 23;2022:9857645. doi: 10.1155/2022/9857645]. Oxid Med Cell Longev. 2017;2017:1716701. doi:10.1155/2017/1716701
- Proline – This amino acid and its metabolite make up about 25% of the amino acids in collagen in bone, connective tissue, and the extracellular matrix.40Albaugh VL, Mukherjee K, Barbul A. Proline precursors and collagen synthesis: Biochemical challenges of nutrient supplementation and wound healing. J Nutr. 2017;147(11):2011-2017.
- Serine – Plays a role in neurotransmission, and folate and methionine cycles.41Holeček M. Serine Metabolism in Health and Disease and as a Conditionally Essential Amino Acid. Nutrients. 2022;14(9):1987. Published 2022 May 9. doi:10.3390/nu14091987
- Tyrosine – In healthy humans, an acute intake of tyrosine increases plasma levels of norepinephrine, epinephrine, and dopamine.42Rasmussen, D. D., Ishizuka, B., Quigley, M. E., and Yen, S. S. Effects of tyrosine and tryptophan ingestion on plasma catecholamine and 3,4-dihydroxyphenylacetic acid concentrations. J.Clin.Endocrinol.Metab 1983;57(4):760-763.
Some non-essential amino acids, such as arginine, are complementary to BCAAs. In one study43Hsu M-C, Chien K-Y, Hsu C-C, et al. Effects of BCAA, Arginine and Carbohydrate Combined Drink on Post-Exercise Biochemical Response and Psychological Condition. Chinese Journal of Physiology. 2011; 54(2): 71-78., a blend of BCAAs, arginine, and carbohydrates was found to promote:
- More optimal levels of glucose and insulin during recovery from training.
- A positive anabolic response during the recovery period.
- Improve fatigue score after exercise.
Conditionally Essential Amino Acids in BCAAs
Amino acids may be considered conditionally essential because the body cannot synthesize them in sufficient quantities during illness, stress, or specific physiological periods of growth, including pregnancy, adolescent growth, or recovery from trauma44de Koning TJ. Amino acid synthesis deficiencies. Handb Clin Neurol. 2013;113:1775-83.. Conditionally essential amino acids include arginine, histidine, cysteine, glutamine, tyrosine, glycine, proline, and serine45Amino acids. MedlinePlus, National Library of Medicine. Reviewed January 19, 2023. Retrieved August 8, 2024 from https://medlineplus.gov/ency/article/002222.htm#:~:text=Nonessential%20means%20that%20our%20bodies,proline%2C%20serine%2C%20and%20tyrosine..
Some non-essential amino acids, such as glutamine, also complement BCAAs. Besides its role as a protein synthesis building block, glutamine provides a ready energy source via its role in generating ATP46Institute of Medicine (US) Committee on Military Nutrition Research. Military Strategies for Sustainment of Nutrition and Immune Function in the Field. Washington (DC): National Academies Press (US); 1999. 47Lee W-C, Guntur AR, Long F, Rosen CJ. Energy Metabolism of the Osteoblast: Implications for Osteoporosis. Endocr Rev. 2017 Jun 1; 38(3): 255–266..
Choosing the Right BCAA for Your Supplements
In research, BCAA supplementation was used in various strategies, including pre-load only, at the exercise day only, at pre-load and exercise day, on the exercise day and recovery period, and at pre-load, exercise day, and recovery period. In any case, seven of the studies included supplementation with BCAA at a ratio of 2:1:1 (leucine: isoleucine: valine), although the BCAA ratio was 3:1:2 in two studies.48Khemtong C, Kuo CH, Chen CY, Jaime SJ, Condello G. Does Branched-Chain Amino Acids (BCAAs) Supplementation Attenuate Muscle Damage Markers and Soreness after Resistance Exercise in Trained Males? A Meta-Analysis of Randomized Controlled Trials. Nutrients. 2021;13(6):1880. Published 2021 May 31. doi:10.3390/nu13061880 Whichever ratio you choose, the data indicates that leucine should be the predominant amino acid.
Vitaquest Excels at Creating Custom BCAA Dietary Supplements
Vitaquest is a contract development and manufacturing organization (CDMO) that has successfully provided thousands of supplement business owners with best-in-class BCAA supplement manufacturing, packaging, and fulfillment services for over 45 years.
Whether you’re a newcomer to the industry or aiming to diversify your product range, Vitaquest possesses the formulation design expertise, cutting-edge facilities, and solutions needed to swiftly and effectively turn your BCAA supplement concept into reality. Vitaquest offers a variety of dosage forms, including capsules, tablets, and powders.
Vitaquest also has expertise in domestic and international regulatory standards. We are GMP-certified by NSF, assuring brand owners and consumers about our compliance with industry regulations and standards. In addition, Vitaquest can offer Kosher, Halal, certified organic products, and FSSC 22000 certification for food safety.
Are you ready to capitalize on the BCAA supplement trends? If so, call 800-526-9095 to speak with one of our knowledgeable sales executives or request a nutraceutical manufacturing price quote if you’ve already finalized your project requirements!
Conclusion
BCAA supplements are extremely popular, and their popularity continues to grow. BCAA are important for protein synthesis, and research has demonstrated their effectiveness in reducing the breakdown of skeletal muscle, decreasing muscle soreness and muscle fatigue after exercise, decreasing lactic acid levels during exercise, and helping maintain lean muscle mass while burning fat.
A combination of the three BCAA types—leucine, isoleucine, and valine—is important to include in a well-formulated product. Make sure to contact Vitaquest if you’re ready to capitalize on the BCAA supplement trends!
Frequently Asked Questions About Different BCAA Types
Q: What is the best type of BCAA?
The best type of BCAA is a formula that contains the three BCAA amino acids: leucine, isoleucine and valine. Furthermore, since most studies were done using a 2:1:1 ratio of these amino acids, this is a good choice.
Q: What are the three branched-chain amino acids?
The three BCAA amino acids are leucine, isoleucine and valine. Most studies were done using a 2:1:1 ratio of these amino acids.
Q: Which BCAA is most anabolic?
Leucine is the most anabolic, but it is best to use leucine, isoleucine, and valine together.
Q: Is BCAA for bulking or cutting?
Both. By helping to stimulate protein synthesis, it is bulking. But, by helping you to maintain muscle while losing weight, it is cutting.
Q: How do I choose BCAA?
Choose a BCAA formula that contains the three amino acids: leucine, isoleucine, and valine. Furthermore, since most studies were done using a 2:1:1 ratio of these amino acids, this is a good choice.
Q: What is healthier–BCAA or creatine?
Both are healthy, and both serve different functions. BCAAs serve as building blocks for muscle tissue, while creatine helps to stimulate muscle growth/repair.
References
- 1Wolfe RR. Branched-chain amino acids and muscle protein synthesis in humans: myth or reality?. J Int Soc Sports Nutr. 2017;14:30. Published 2017 Aug 22. doi:10.1186/s12970-017-0184-9
- 2Branched Chain Amino Acids (BCAAs) Market Size Global Market Insights. Retrieved August 8, 2024 from https://www.gminsights.com/industry-analysis/branched-chain-amino-acids-market#:~:text=Branched%20Chain%20Amino%20Acids%20Market%20size%20was%20valued%20at%20USD,CAGR%20from%202023%20to%202032.
- 3Neinast M, Murashige D, Arany Z. Branched Chain Amino Acids. Annu Rev Physiol. 2019;81:139-164. doi:10.1146/annurev-physiol-020518-114455
- 4Raizel R, Coqueiro AY, Bonvini A, Tirapegui J. 1 - Sports and Energy Drinks: Aspects to Consider. In Sports and Energy Drinks. Volume 10: The Science of Beverages. Woodhead Publishing; 2019:1-37.
- 5Louard RJ, Barrett EJ, Gelfand RA.Overnight branched-chain amino acid infusion causes sustained suppression of muscle proteolysis. Metabolism 1995;44(4):424-9.
- 6MacLean DA, Graham TE, Saltin B. Branched-chain amino acids augment ammonia metabolism while attenuating protein breakdown during exercise. Am J Physiol 1994;267:E1010-22.
- 7Greer BK, Woodard JL, White JP, Arguello EM, Haymes EM. Branched-chain amino acid supplementation and indicators of muscle damage after endurance exercise. Int J Sport Nutr Exerc Metab 2007;17(6):595-607.
- 8Coombes JS, McNaughton LR. Effects of branched-chain amino acid supplementation on serum creatine kinase and lactate dehydrogenase after prolonged exercise. J Sports Med Phys Fitness 2000;40(3):240-6.
- 9Shimomura Y, Murakami T, Nakai N, Nagasaki M, Harris RA. Exercise promotes BCAA catabolism: effects of BCAA supplementation on skeletal muscle during exercise. J Nutr 2004 Jun;134(6 Suppl):1583S-1587S.
- 10Tang FC. Influence of branched-chain amino acid supplementation on urinary protein metabolite concentrations after swimming. J Am Coll Nutr 2006;25(3):188-94.
- 11Shimomura Y, Murakami T, Nakai N, Nagasaki M, Harris RA. Exercise promotes BCAA catabolism: effects of BCAA supplementation on skeletal muscle during exercise. J Nutr 2004 Jun;134(6 Suppl):1583S-1587S.
- 12Shimomura Y, Yamamoto Y, Bajotto G, Sato J, Murakami T, Shimomura N, Kobayashi H, Mawatari K. Nutraceutical effects of branched-chain amino acids on skeletal muscle. J Nutr 2006;136(2):529S-532S.
- 13MacLean DA, Graham TE, Saltin B. Stimulation of muscle ammonia production during exercise following branched-chain amino acid supplementation in humans. J Physiol 1996;493(Pt 3):909-22.
- 14De Palo EF, Gatti R, Cappellin E, Schiraldi C, De Palo CB, Spinella P. Plasma lactate, GH and GH-binding protein levels in exercise following BCAA supplementation in athletes. Amino Acids 2001;20(1):1-11.
- 15Coombes JS, McNaughton LR. Effects of branched-chain amino acid supplementation on serum creatine kinase and lactate dehydrogenase after prolonged exercise. J Sports Med Phys Fitness 2000;40(3):240-6.
- 16Koba T, Hamada K, Sakurai M, Matsumoto K, Hayase H, Imaizumi K, Tsujimoto H, Mitsuzono R. Branched-chain amino acids supplementation attenuates the accumulation of blood lactate dehydrogenase during distance running. J Sports Med Phys Fitness 2007;47(3):316-22.
- 17Lopez MJ, Mohiuddin SS. Biochemistry, Essential Amino Acids. [Updated 2024 Apr 30]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK557845/
- 18Volpi E, Mittendorfer B, Wolf SE, Wolfe RR. Oral amino acids stimulate muscle protein anabolism in the elderly despite higher first-pass splanchnic extraction. Am J Physiol. 1999 Sep;277(3 Pt 1):E513-20.
- 19Paddon-Jones D, Sheffield-Moore M, Zhang XJ, Volpi E, Wolf SE, Aarsland A, Ferrando AA, Wolfe RR. Amino acid ingestion improves muscle protein synthesis in the young and elderly. Am J Physiol Endocrinol Metab. 2004 Mar;286(3):E321-8.
- 20Paddon-Jones D, Sheffield-Moore M, Zhang XJ, Volpi E, Wolf SE, Aarsland A, Ferrando AA, Wolfe RR. Amino acid ingestion improves muscle protein synthesis in the young and elderly. Am J Physiol Endocrinol Metab. 2004 Mar;286(3):E321-8.
- 21Paddon-Jones D, Sheffield-Moore M, Katsanos CS, Zhang XJ, Wolfe RR. Differential stimulation of muscle protein synthesis in elderly humans following isocaloric ingestion of amino acids or whey protein. Exp Gerontol. 2006 Feb;41(2):215-9.
- 22Hirsch KR, Greenwalt CE, Saylor HE, Gould LM, Harrison CH, Brewer GJ, Blue MNM, Ferrando AA, Huffman KM, Mayer-Davis EJ, Ryan ED, Smith-Ryan AE. High-intensity interval training and essential amino acid supplementation: Effects on muscle characteristics and whole-body protein turnover. Physiol Rep. 2021 Jan;9(1):e14655.
- 23Khemtong C, Kuo CH, Chen CY, Jaime SJ, Condello G. Does Branched-Chain Amino Acids (BCAAs) Supplementation Attenuate Muscle Damage Markers and Soreness after Resistance Exercise in Trained Males? A Meta-Analysis of Randomized Controlled Trials. Nutrients. 2021;13(6):1880. Published 2021 May 31. doi:10.3390/nu13061880.
- 24Novin ZS, Ghavamzadeh S, Mehdizadeh A. The Weight Loss Effects of Branched Chain Amino Acids and Vitamin B6: A Randomized Controlled Trial on Obese and Overweight Women. Int J Vitam Nutr Res. 2018;88(1-2):80-89. doi:10.1024/0300-9831/a000511
- 25Lim CH, Gil JH, Quan H, Viet DH, Kim CK. Effect of 8-week leucine supplementation and resistance exercise training on muscle hypertrophy and satellite cell activation in rats. Physiol Rep. 2018;6(12):e13725. doi:10.14814/phy2.13725
- 26Ispoglou T, White H, Preston T, McElhone S, McKenna J, Hind K. Double-blind, placebo-controlled pilot trial of L-Leucine-enriched amino-acid mixtures on body composition and physical performance in men and women aged 65-75 years. Eur J Clin Nutr. 2016;70(2):182-188. doi:10.1038/ejcn.2015.91
- 27Pathak K, Zhao Y, Calton EK, et al. The impact of leucine supplementation on body composition and glucose tolerance following energy restriction: an 8-week RCT in adults at risk of the metabolic syndrome. Eur J Clin Nutr. 2024;78(2):155-162. doi:10.1038/s41430-023-01360-1
- 28Gu C, Mao X, Chen D, Yu B, Yang Q. Isoleucine Plays an Important Role for Maintaining Immune Function. Curr Protein Pept Sci. 2019;20(7):644-651. doi:10.2174/1389203720666190305163135
- 29Isoleucine. Healthy Encyclopedia. University of Rochester Medical Center. Retrieved August 8, 2024 from https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=19&contentid=Isoleucine.
- 30Sharma S, Zhang X, Azhar G, et al. Valine improves mitochondrial function and protects against oxidative stress. Biosci Biotechnol Biochem. 2024;88(2):168-176. doi:10.1093/bbb/zbad169
- 31Lopez MJ, Mohiuddin SS. Biochemistry, Essential Amino Acids. [Updated 2024 Apr 30]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK557845/
- 32Amino acids. MedlinePlus, National Library of Medicine. Reviewed January 19, 2023. Retrieved August 8, 2024 from https://medlineplus.gov/ency/article/002222.htm#:~:text=Nonessential%20means%20that%20our%20bodies,proline%2C%20serine%2C%20and%20tyrosine.
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