What are the benefits of BCAAs (Branched-Chain Amino Acids)
Updated: Jan 30, 2021
An Olympic weight lifter needs to monitor their diet, one element of focus is the BCAA within their food, but what do they do?
Twenty different amino acids make thousands of different proteins in the human body. Nine of the 20 are considered essential amino acids, meaning they cannot be made by the body and must be obtained through diet (Van, 2018). The nine essential amino acids are made of three branched-chain amino acids (BCAAs): leucine, isoleucine and valine. "Branched-chain" refers to the chemical structure of BCAAs, which are found in protein-rich foods such as eggs, meat and dairy products (Van, 2018). They sold in powder form as a supplement available online or in local stores.
One of the most popular uses of BCAAs is to increase muscle growth.
The leucine activates a specific pathway in the body that stimulates muscle protein synthesis, making muscle (Van, 2018). In one study, people who consumed a drink with 5.6 grams of BCAAs after their resistance workout had a 22% greater increase in muscle protein synthesis than those who consumed a placebo drink (VanDusseldorp et al., 2018). That being said, this increase in muscle protein synthesis is approximately 50% less than what was observed in other studies where people consumed a whey protein shake containing a similar amount of BCAAs. Whey protein contains all the essential amino acids needed to build muscle (Gangurde et al., 2011). Therefore, while BCAAs can increase muscle protein synthesis, they cannot do so maximally without the other essential amino acids, such as those found in whey protein or other complete protein sources.
Some research suggests that BCAAs can help decrease muscle soreness after a workout. It is not uncommon to feel sore a day or two after a workout, especially if the exercise routine is new. This soreness is called delayed onset muscle soreness (DOMS), which develops 12 to 24 hours after exercise and can last up to 72 hours. While the exact cause of DOMS is not clearly understood, researchers believe it results from tiny tears in the muscles after exercise.
BCAAs have been shown to decrease muscle damage, which may help reduce the length and severity of DOMS.
In one study, people who supplemented with BCAAs before a squat exercise experienced reduced DOMS and muscle fatigue than the placebo group (Shimomura et al., 2010). Therefore, supplementing with BCAAs, especially before exercise, BCCA supplementation may also help reduce exercise-induced fatigue. Everyone experiences fatigue and exhaustion from exercise at some point. How quickly the body tires depends on certain factors, including exercise intensity and duration, conditions in the training environment and nutrition, and the conditioning level of the muscles. Muscles use BCAAs during exercise, causing levels in the blood to decrease. When blood levels of BCAAs decline, the essential amino acid tryptophan levels in the brain increase (Shimomura et al., 2004).
In the brain, tryptophan is converted to serotonin, a brain chemical that contributes to fatigue development during exercise.
In two studies, participants who supplemented with BCAAs improved their mental focus during exercise, which is thought to result from the fatigue-reducing effect of BCAAs (Shimomura et al., 2010).
However, this lack of fatigue is unlikely to translate to improvements within training performance. BCAAs can help prevent muscle wasting or breakdown. Muscle proteins are frequently broken down and resynthesized. The balance between muscle protein breakdown and synthesis determines the amount of protein in muscle. Muscle wasting or breakdown occurs when protein breakdown exceeds muscle protein synthesis. Muscular wasting is a sign of malnutrition and occurs with chronic infections, cancer, fasting periods, and a natural part of the ageing process. In humans, BCAAs account for 35% of the essential amino acids found in muscle proteins. They account for 40% of the total amino acids required by the body. Therefore, the BCAAs and other essential amino acids must be replaced during muscle wasting to halt it or slow its progression. Several studies support the use of BCAA supplements for inhibiting muscle protein breakdown (Wolfe, 2017).
Summary for taking a BCAA supplement.
It can prevent the breakdown of protein in specific populations with muscle wasting. However, Olympic weightlifting athletes should be recommended for better performance within their training or competing at whatever level. BCCAs have shown over several years that weightlifters the better the blood and performance is.
VanDusseldorp, T., Escobar, K., Johnson, K., Stratton, M., Moriarty, T., Cole, N., McCormick, J., Kerksick, C., Vaughan, R., Dokladny, K., Kravitz, L. and Mermier, C. (2018). Effect of Branched-Chain Amino Acid Supplementation on Recovery Following Acute Eccentric Exercise. Nutrients, [online] 10(10), p.1389. Available at: https://www.mdpi.com/2072-6643/10/10/1389 [Accessed 30 Jan. 2021].
Van, G. (2018). 5 Proven Benefits of BCAAs (Branched-Chain Amino Acids). [online] Healthline. Available at: https://www.healthline.com/nutrition/benefits-of-bcaa [Accessed 30 Jan. 2021].
GANGURDE, H., CHORDIYA, M., PATIL, P. and BASTE, N., (2011). Whey protein. Scholars' Research Journal, 1(2). p.1
Shimomura, Y., Murakami, T., Nakai, N., Nagasaki, M. and Harris, R.A. (2004). Exercise Promotes BCAA Catabolism: Effects of BCAA Supplementation on Skeletal Muscle during Exercise. The Journal of Nutrition, 134(6), p.1583-1587.
Shimomura, Y., Inaguma, A., Watanabe, S., Yamamoto, Y., Muramatsu, Y., Bajotto, G., Sato, J., Shimomura, N., Kobayashi, H. and Mawatari, K. (2010). Branched-Chain Amino Acid Supplementation Before Squat Exercise and Delayed-Onset Muscle Soreness. International Journal of Sports Nutrition and Exercise Metabolism, 20(3), p.236–244.
Wolfe, R.R. (2017). Branched-chain amino acids and muscle protein synthesis in humans: myth or reality? Journal of the International Society of Sports Nutrition, 14(1).