BCAA (Branch Chain Amino Acid)


Branch Chain Amino Acids consist of three separate amino acids: Leucine, Isoleucine, and Valine. These amino acids are considered “essential” because the body cannot manufacture them and thus, they must be obtained from our diet.

Leucine helps in the regulation of protein turnover and energy metabolism. It also helps inhibit the breakdown of muscle protein that occurs after high stress.

“A lot of lifters want to take BCAA while exercising largely through epicricial observation is because it enhances muscle growth and prevents muscle degradation during exercise.  It turns out (the below) isolecine and valine are irrelevant – its pretty much all leucine. From a nutrient sensing pathway what you can infer from that is too little leucine – probably a bad thing, too much leucine – probably a bad thing. Now what too much and too little are remains to be seen. Can we take too much leucine during our workout? I dont think we know the answer but extrapolating from the animal data about 5g of leucine during a workout probably not harmful. It also doesn’t stick around long in the body because its a free amino acid with a relatively short stay in the body.

(Source: Peter Attia, M.D. on Macronutrient Thresholds for Longevity and Performance, Cancer and More)

Isoleucine’s main purpose is that of an antioxidant.

Valine improves energy metabolism and protein synthesis, and like Leucine, helps maintain muscle strength during times of high intensity physical stress.

Branch chain amino acids are found in high concentrations primarily in the skeletal muscle tissue. These BCAAs account for 35-40% of the dietary essential amino acids in body protein and 14-18% of the total amino acids in muscle proteins.


As our muscles burn up the available stores of BCAA’s in the body during exercise, they begin to break down skeletal muscle tissue in order to provide the essential amino acids to fuel more exercise. This cell damage results in reduced ability to contract and relax during intense stress, resulting in muscle fatigue, lactic acidosis, loss of performance and delayed recovery as muscle tissue repairs itself. Generally, these branched chain amino acids are muscle synthesis, muscle growth, and muscle repair. More specifically these BCAA’s perform numerous functions, though they are not used as a primary energy source (as shown above), they are definitely an important fuel source for skeletal muscle during periods of extreme exertion. During these periods of stress, BCAAs help promote protein synthesis while helping to suppress its catabolism and serve as substrates for gluconeogenesis. The catabolism of the BCAAs in skeletal muscle plays a key role in the formation of glutamine which is one of the glucogenic amino acids. Other functions include; increased endurance resulting in delayed fatigue during exercise, improved mental performance, energy levels, immune system function, and finally, post exercise recovery. Post exercise recovery means less muscle soreness and fewer upper respiratory tract infections.


Many experiments have been done to the look at the effects of BCAAs. For example, one experiment gave branched chain amino acids or a placebo to 7 subjects during 1 hour of cycle ergometer exercise and during a two-hour recovery period. The intake of the BCAA did not influence the rate of exchange of the aromatic amino acids during exercise or increase their muscle concentration. However, during the recovery period, a faster decrease of the concentration of the aromatic amino acids was found within the BCAA group. The results suggest that BCAA have a protein-sparing effect during the recovery after exercise, either that protein synthesis has been stimulated and/or protein degradation has decreased.

A second test was given to 14 healthy male and 16 healthy female adults, between the ages of 21-24 years old, who do not participate in regular exercise. The test performed were squats to induce delayed onset muscle soreness (DOMS) and muscle fatigue. Subjects were given either a BCAA mixture or a placebo that was to be consumed 15 minutes prior to exercise. The results of this study indicate that the ingestion of the 5g of BCAAs previous to exercise can reduce DOMS and muscle fatigue for several days after exercise.

One study gave a group of trained triathletes 6g of BCAA per day for one month prior to competition, then 3g of BCAA from the day of competition to a week after. As compared with a placebo group timing the placebo for the same length of time, the BCAAs restored depleted glutamine stores and immune factors that occur in elite athletes. This study also suggested that may improve exercise induced declines of mental functioning.

Lastly, one study tested 13 subjects whom ingested either a BCAA mixture or a placebo prior to endurance exercise in the heat. On average, the BCAA group cycled 153.1 minutes while the placebo group only cycled for an average of 137.0 minutes.

BCAA for hunger pains carb / sugar desires

Consume a small amount (3-5g) of BCAA to stave the carvings off and the liver will convert the BCAA’s into glycogen.