Longevity logo

The Science Behind BCAAs

Branch Chain Amino Acids

By Kevin ArmentroutPublished 5 years ago 7 min read

I get asked all the time, “What supplements should I take?” If I have ever talked with you, or you’ve looked around our site, you will see the supplements I always recommend, that I refer to as, the essentials. The essentials are a multi-vitamin, fish oils, and a quality protein. These aren’t supplements that I consider to be for a specific goal, but rather a part of essential living, hence the name. They will benefit you in all terms of health, wellness, and metabolism. Now, there are supplements I recommend that will aid in specific goals and performance. The number one supplement that will enhance any training program, goal, or level of performance, is branch chain amino acids or BCAAs.

BCAAs are comprised of three essential amino acids: Leucine, Isoleucine, and Valine. Essential amino acids cannot be produced by the body and must be ingested from a dietary source. BCAAs are amino acids, so they are found in proteins with the highest concentration of BCAAs being found in animal products, like cheeses and red meats. So, if BCAAs are found in proteins and you’re in a high protein diet (which you should be), you may be asking yourself, why would I need to supplement them. The answer, is you don’t, but you should. There is a reason the essential supplements are the essential supplements, but we're talking about maximizing performance, enhancing training, and reaching goals faster. So, the real answer to the question of why, is BCAAs…

  • Enhance Muscle Protein Synthesis
  • Increase Fat Burning and Support Fat Loss
  • Leucine Equalizes Muscle Growth with Age
  • Supports Hormone Balance during Intense Training
  • Improves Strength Development
  • Enhance Endurance & Decrease Fatigue
  • Improve Muscle Recover & Decrease Soreness
  • Prevent Muscle Loss During Intense Training
  • Improve Overall Health and Aging

BCAAs are essential to protein synthesis. Combining BCAAs with resistance training, which also improves protein synthesis, will maximize your muscle building potential. Because BCAAs trigger protein synthesis even when exercise is not present, the preservation of muscle tissue, an increase in your metabolism, and can keep fat stores to a minimum even when inactive. Studies show that BCAAs in rodents who were made to be immobile for an extended period of time, had less muscle atrophy and less fat gain then test subjects without. This is how BCAAs can increase fat burning when supplemented in your daily nutrition. Leucine increases energy expenditure and fat oxidation, and Isoleucine improves glucose tolerance. It has been said in scientific studies that BCAAs appear to have unique obesity-reducing effects.

It’s understood that muscles will use BCAAs as energy during intense resistance training and would make it ideal for performance to have large amounts in reserve. Since BCAAs can be used as energy, maintaining ATP energy levels during exercise becomes more efficient. BCAAs can also enhance the body’s ability to oxidize fat as energy giving you a larger pool overall. The real key factor to enhanced endurance is BCAAs role in reducing central fatigue of the nervous system, by inhibiting uptake of tryptophan. Tryptophan increases tired and fatigue in the brain, and is a big reason we tend to “give out” during training. Participants who took 300mg a day of BCAAs for 3 days performed 17% better during exhaustive exercise then the group without. In addition to improving endurance performance, BCAAs prevent muscle loss during prolonged endurance training, due to the extended energy pool and limit catabolic effects on the muscles.

With increased endurance, comes increased strength. A study of young men supplementing 4g/day of Leucine gained more strength than a placebo group after 12 weeks of training. A staggering increase of 31% more on all exercises. Leucine is known to increase protein synthesis by up to 145% when taking after strength training. Leucine enriched BCAAs has also been shown to elevate and prolong protein synthesis even in older people. As we age muscle producing becomes harder to do, yet it’s essential to continuing a healthy lifestyle. So BCAAs that have higher than 30% Leucine (3:1:1 ration or greater) are essential to building muscle with age. Just as protein synthesis begins to decline with age so do our hormone levels. BCAAs support hormone balance in the body in response to intense training. A study showed that a group who loaded 6g/day of BCAAs for 3 weeks followed by high-intensity training for 1 week, had higher testosterone levels and lower cortisol, with lower markers of inflammation. The inflammation is an indicator of BCAAs ability to aid recovery and reduce muscle soreness. A study of women who were not familiar with resistance training, showed a reduction in muscle soreness with BCAAs compared to the untrained women without. This all points to better stress adaptation, increased muscle building, and hormonal balance in the body, regardless of sex and even with age.

The BCAA Isoleucine improves glucose tolerance, and BCAAs as a whole support insulin sensitivity and metabolism for improved body composition. Studies have shown that individuals in weight loss programs that have had the greatest weight loss and improvements in body composition and insulin sensitivity, also had the highest levels of BCAAs.

Note: Diabetics have dysfunctional BCAA metabolism, and taking BCAAs can elevate insulin.

At the end of the day no matter what your training regimen is like, or what you are trying to achieve, BCAAs will benefit you. If you’re new to fitness and looking to lose weight, BCAAs will help you recover faster when you first start training, where you undoubtedly will be sore. They will increase your energy to get you through your workouts, and increase your metabolism, helping you burn more fat. BCAAs will help increase muscle building and getting you to your goals faster. If you’re looking to maintain your level of health and fitness, BCAAs will balance your hormones and prolong lifespan. If you are looking to put on some serious muscle and you’re not already taking BCAAs, stop right now and go get some, period.

Relentless State of Mind: The Power of Mental Conditioning

Pick up a copy of my new book, and create an unstoppable mind.


Valerio, A., D’antona, G., et al. BCAAs, Mitochondrial Biogenesis, and Healthspan: An Evolutionary Perspective. Aging. May 2011. 3(5), 464-470.

Bajotto, G., Sato, Y., et al. Effect of BCAA Supplementation During Unloading on Regulatory Components of Protein Synthesis in Atrophied Soleus Muscles. European Journal of Applied Physiology. 2011. 111, 1815-1828.

Borgenvik, M., Nordin, M., et al. Alterations in Amino Acid Concentrations in the Plasma and Muscle in Human Subjects during 24 Hour of Simulated Adventure Racing. European Journal of Applied Physiology. 2012. Published Ahead of Print.

Da Luz, Claudia, Nicastro, H., et al. Potential Therapeutic Effects of BCAA Supplementation on Resistance Exercise-Based Muscle Damage in Humans. Journal of the International Society of Sports Nutrition. 2011. 8(23).

Gualano, A, et al. Branched-Chain Amino Acids Supplementation Enhances Exercise Capacity and Lipid Oxidation During Endurance Exercise After Muscle Glycogen Depletion. Journal of Sports Medicine and Physical Fitness. 2011.51 (5), 82-88.

Hsu, M., Chien, K., et al. Effects of BCAA, Arginine, and Carbohydrate Combined Drink on Post-Exercise Biochemical Response and Psychological Condition. Chinese Journal of Physiology. April 2011. 542), 71-78.

Glynn, E., Fry, C., Drummond, M., Timmerman, K., Dhanani, S., Volpi, E., Rasmussen, B. Excess Leucine Intake Enhances Muscle Anabolic Signaling but Not Net Protein Anabolism in Young Men and Women. The Journal of Nutrition. 2010. 140(11), 1970-1976.

Sharp, C., Pearson, D. Amino Acid Supplements and Recovery from High-Intensity Resistance Training. Journal of Strength and Conditioning Research. 2010. 24(4), 1125-1130.

lpoglou, T., King, R., Polman, R., Zanker, C. Daily L-Leucine Supplementation in Novice Trainees During a 12-Week Weight Training Program. International Journal of Sports Physiology and Performance. 2011. 6(1 ), 38-80.

Jourdan, C., et al. Body Fat Free Mass is Associated with the Serum Metabolite Profile in A Population Based Study. PLOS One. 2012. 7(6), e40009


About the Creator

Reader insights

Be the first to share your insights about this piece.

How does it work?

Add your insights


There are no comments for this story

Be the first to respond and start the conversation.

Sign in to comment

    Find us on social media

    Miscellaneous links

    • Explore
    • Contact
    • Privacy Policy
    • Terms of Use
    • Support

    © 2023 Creatd, Inc. All Rights Reserved.