BCAA is an abbreviation for branched chain amino acids -- leucine, isoleucine, and valine -- which have anabolic effects on protein metabolism by increasing the rate of protein synthesis and decreasing the rate of protein degradation in resting human muscle. Also, during recovery from endurance exercise, BCAA have anabolic effects in human muscle. These effects are likely to be mediated through changes in signaling pathways controlling protein synthesis. BCAAs are widely found in dairy foods and meat and are also available in capsules or powder.

BCAA supplement for muscle training, growth and strength
J Int Soc Sports Nutr. 2016. In a single-blind, matched group design: branched-chain amino acid supplementation and resistance training maintains lean body mass during a caloric restricted diet. Athletes and active adults many times have the goal of improving/maintaining fitness while losing weight and this is best achieved by caloric restriction in combination with exercise. However, this poses a risk for lean tissue loss, which can limit performance. Thus, the purpose of this study was to determine the effectiveness of a branched-chain amino acid (BCAA) supplement, in conjunction with heavy resistance training and a carbohydrate caloric-restricted "cut diet" on body composition and muscle fitness. Seventeen resistance-trained males (21-28 years of age) were randomized to a BCAA group (n = 9) or a carbohydrate (CHO) group (n = 8) who both received their respective supplement during the 8 weeks of a prescribed body building style resistance training protocol. Subjects were prescribed a hypocaloric diet (based upon pre-intervention analysis) that was to be followed during the study. Results show that BCAA supplementation in trained individuals performing resistance training while on a hypocaloric diet can maintain lean mass and preserve skeletal muscle performance while losing fat mass.

Athletes who supplement with branched-chain amino acids while a moderate endurance workout could help reduce muscle breakdown. Dr. Keitaro Matsumoto of Otsuka Pharmaceutical Company in Saga, Japan had four men and four women complete three 20-minute cycling sessions, pedaling at half their maximum intensity, with a 15-minute break between each session. During the first exercise session, volunteers supplemented with a drink containing 2 grams of BCAAs and 0.5 gram of arginine, or a placebo beverage, 10 minutes into their workout. Two weeks later, study participants repeated the experiment, and those who originally consumed the BCAA-arginine drink switched to placebo and vice versa. Blood concentration and muscle absorption of BCAAs rose when the exercisers took the supplement, while muscle protein breakdown was reduced. International Journal of Sports Medicine, June 2007.

The authors examined the effect of branched-chain amino acid supplementation on squat-exercise-induced delayed-onset muscle soreness (DOMS) using 12 young, healthy, untrained female participants. In the morning on the exercise-session day, the participants ingested either BCAA (isoleucine:leucine:valine = 1:2.3:1.2) or dextrin at 100 mg/kg body weight before the squat exercise, which consisted of 7 sets of 20 squats / set with 3-minute intervals between sets. DOMS showed a peak on Days 2 and 3 in both trials, but the level of soreness was significantly lower in the BCAA trial than in the placebo. Our results suggest that muscle damage may be suppressed by BCAA supplementation. Int J Sport Nutr Exercise Metab. 2010. Branched-chain amino acid supplementation before squat exercise and delayed-onset muscle soreness. Dept. of Applied Molecular Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan.

I am a 40 yr old male with a well build body type. I am considered a bit sporty and im giving my time a share in the gym doing some exercises and lifting(1-2 hours)...I am taking BCAA 1000 mg pill 2 before and 2 pills after workout. and one drink of whey protein early in the morning before breakfast. I'm thinking of adding creatine 1500 mg just before the exercise to get some muscle mass, but the thing is that creatine users rather speaks badly about it after some time as reported on some web sites.
    Creatine supplements, used reasonably, have been found safe and effective as muscle builders.

Recovery after endurance exercise
Branched-chain amino acid supplementation and indicators of muscle damage after endurance exercise.
Int J Sport Nutr Exerc Metab. 2007. Dept. of Physical Therapy and Human Movement Sciences, Sacred Heart University, Fairfield, CT, USA.
The purpose of this study was to determine whether branched-chain amino acid BCAA supplementation attenuates indirect indicators of muscle damage during endurance exercise as compared with an isocaloric, carbohydrate (CHO) beverage or a noncaloric placebo beverage. Nine untrained men performed three 90 min cycling bouts at 55% VO 2peak. The volunteers blinded to beverage selection, ingested a total of 200 kcal of energy via the CHO or BCAA beverage before and at 60 min of exercise, or they drank the placebo beverage. Creatine kinase (CK), lactate dehydrogenase (LDH), isokinetic leg-extension and -flexion torque, and muscle soreness were assessed before and immediately, 4 h, 24 h, and 48 h postexercise. CK activities were significantly lower after the BCAA trial at 4, 24, and 48 h postexercise, as well as lower than the CHO beverage at 24 h postexercise. CK was lower in the CHO trial at the 24- and 48-h time points than in the placebo trial. LDH activities were lower in the BCAA trial at 4 h. As compared with the CHO and placebo trials, ratings of perceived soreness were lower at 24 h postexercise, and leg-flexion torque was higher at the 48-h time point after the BCAA trial. The present data suggest that supplementation attenuates muscle damage during prolonged endurance exercise in untrained college-age men.

Cancer surgery
Response of muscle protein and glutamine kinetics to branched chain enriched amino acids - BCAA - in intensive care patients after radical cancer surgery.
Nutrition. 2006 May. Department of Clinical, Technological and Morphological Sciences, Division of Internal Medicine, University of Trieste, Trieste, Italy.
Patients with cancer are characterized by decreased muscle protein synthesis and glutamine availability that contribute to an impaired immune response. These abnormalities worsen after surgical stress. We tested the hypothesis that pharmacologic doses of branched-chain amino acids would improve the early metabolic response after major cancer surgery. An excess of branched-chain amino acids in the presence of an optimal profile of other essential amino acids acutely increased muscle protein synthesis and glutamine flux from skeletal muscle in cancer patients after surgery.

Diabetes and blood sugar
Am J Epidemiol. 2013 Oct 15. Branched-chain amino acid intake and the risk of diabetes in a Japanese community: the Takayama study. Dietary supplementation with branched-chain amino acids (BCAAs), including leucine, isoleucine, and valine, has shown potential benefits for the metabolic profile. However, higher blood BCAA levels have been associated with insulin resistance. To our knowledge, there has been no study on dietary BCAAs and the risk of diabetes. We examined the association between BCAA intake and risk of diabetes in a population-based cohort study in Japan. A total of 13,525 residents of Takayama City, Japan, who enrolled in a cohort study in 1992 responded to a follow-up questionnaire seeking information about diabetes in 2002. Diet at baseline was assessed by means of a validated food frequency questionnaire. A high intake of BCAAs in terms of percentage of total protein was significantly associated with a decreased risk of diabetes in women after controlling for covariates; the hazard ratio for the highest tertile versus the lowest was 0.57. In men, leucine intake was significantly marginally associated with the risk of diabetes; the hazard ratio for the highest tertile versus the lowest was 0.70. Data suggest that a high intake of BCAAs may be associated with a decrease in the risk of diabetes.

Fatigue
A role for branched chain amino acids in reducing central fatigue.
J Nutr. 2006. Astrand Laboratory, University College of Physical Education and Sports and Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
Several factors have been identified to cause peripheral fatigue during exercise, whereas the mechanisms behind central fatigue are less well known. Changes in the brain 5-hydroxytryptamine (5-HT) level is one factor that has been suggested to cause fatigue. The rate-limiting step in the synthesis of 5-HT is the transport of tryptophan across the blood-brain barrier. This transport is influenced by the fraction of tryptophan available for transport into the brain and the concentration of the other large neutral amino acids, including the BCAA (leucine, isoleucine, and valine), which are transported via the same carrier system. Studies in human subjects have shown that the plasma ratio of free tryptophan (unbound to albumin) / BCAA increases and that tryptophan is taken up by the brain during endurance exercise, suggesting that this may increase the synthesis of 5-HT in the brain. Ingestion of BCAA increases their concentration in plasma. This may reduce the uptake of tryptophan by the brain and also 5-HT synthesis and thereby delay fatigue. Accordingly, when BCAA were supplied to human subjects during a standardized cycle ergometer exercise their ratings of perceived exertion and mental fatigue were reduced, and, during a competitive 30-km cross-country race, their performance on different cognitive tests was improved after the race. In some situations the intake of BCAA also improves physical performance. The results also suggest that ingestion of carbohydrates during exercise delays a possible effect of BCAA on fatigue since the brain's uptake of tryptophan is reduced.

COPD patients
Supplementation of soy protein with branched-chain amino acids alters protein metabolism in healthy elderly and even more in patients with chronic obstructive pulmonary disease. American Journal of Clinical Nutrition, 2007. Surgery and Respiratory Medicine, Maastricht University, Maastricht, The Netherlands; the department of Internal Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; and the Center for Translational Research on Aging and Longevity, the Donald W Reynolds Institute on Aging, University of Arkansas for Medical Sciences, University of Arkansas, Little Rock, AR.
The aim was to examine whether adding BCAA supplement to a soy protein meal would enhance protein anabolism in COPD patients and in healthy elderly persons. Eight normal-weight COPD patients and 8 healthy control subjects were examined on 2 test days. Soy feeding induced a reduction in whole-body protein breakdown and an increase in whole-body protein synthesis. BCAA supplementation of soy protein resulted in a significantly higher increase in whole-body protein synthesis than did soy protein alone in COPD patients but not in the healthy elderly. BCAA supplementation did not significantly alter the change in whole-body protein breakdown or net whole-body protein synthesis. Conclusion: BCAA supplementation to soy protein enhances whole-body protein synthesis in patients with COPD and alters interorgan protein metabolism in favor of the peripheral (muscle) compartment in healthy elderly and even more in COPD patients.

Liver disease, hepatitis, cancer
Oral branched-chain amino acid supplementation improves the oxidized/reduced albumin ratio in patients with liver cirrhosis.
Hepatol Res. 2007; Fukushima H, Miwa Y, Shiraki M, Gomi I, Nakamura H, Wakahara T. Department of Internal Medicine, Gifu Uinversity Graduate School of Medicine, Gifu, Japan.
Branched-chain amino acid supplementation improves hypoalbuminemia in decompensated cirrhotic patients. Recently, it was clarified that the ratio of oxidized albumin within total albumin rises with progression of liver cirrhosis. We conducted a feasibility study to investigate whether BCAA supplementation might improve this ratio. Seven elderly cirrhotic patients with hepatitis C in six and non-B/non-C hepatitis virus in one; Child-Pugh classification: A in six and B in one, were given 4 grams BCAA after each meal for 8 weeks. Serum total, oxidized and reduced albumin, plasma amino acids, glutathione, zinc, selenium, and lipid peroxide concentrations were measured every 2 weeks. Low total albumin, high oxidized albumin, and low reduced albumin levels were observed at entry. After 8 weeks BCAA supplementation, the ratio of oxidized albumin within total albumin decreased significantly and that of reduced albumin increased significantly. Total albumin tended to rise and lipid peroxide concentrations tended to fall, but not significantly. BCAA supplementation improved the oxidized / reduced state of serum albumin. This intervention is effective to maintain the quality of serum albumin in cirrhotic patients.

World J Gastroenterol. 2013. Branched-chain amino acids in liver diseases. Branched chain amino acids (BCAAs) have been shown to affect gene expression, protein metabolism, apoptosis and regeneration of hepatocytes, and insulin resistance. They have also been shown to inhibit the proliferation of liver cancer cells in vitro, and are essential for lymphocyte proliferation and dendritic cell maturation. In patients with advanced chronic liver disease, BCAA concentrations are low, whereas the concentrations of aromatic amino acids such as phenylalanine and tyrosine are high, conditions that may be closely associated with hepatic encephalopathy and the prognosis of these patients. Based on these basic observations, patients with advanced chronic liver disease have been treated clinically with BCAA-rich medicines, with positive effects.

Cancer Chemother Pharmacol. 2014. Importance of branched-chain amino acids in patients with liver cirrhosis and advanced hepatocellular carcinoma receiving hepatic arterial infusion chemotherapy. Branched-chain amino acids might improve survival by increasing serum albumin.

Mol Med Rep. 2015. Effects of branched-chain amino acids and zinc-enriched nutrients on prognosticators in HCV-infected patients: A multicenter randomized controlled trial. BCAA and zinc‑enriched supplementation may prolong the survival of hepatitis C virus infected patients by improving amino acid imbalance and zinc deficiency.

Side effects, risk
No major safety issues or side effects have been published in medical journals as of 2011.

ADHD
I am considering starting a multivitamin and beginning a work out regiment, I also have Adult ADHD. I was wondering if I should consider the use of a multivitamin with BCAA in it. My reason for this was not for the possibility of protein and muscle building in my workout, but for the possibility of utilizing the Amino acids to influence brain function and possibly CNS stimulation. I read over both areas on the subjects of BCAA and ADHD and you do not link the two as having anything in common. However I considered the possibility. Could this help and is there anything bad that could happen from taking BCAA supplements?
   We have not yet seen any research regarding the relationship of a BCAA supplement to ADHD.

Depression and mood
I'm a weightlifter who also takes tryptophan (for its sleep, anti-anxiety and anti-depressant properties), tyrosine (lack of motivation) and occasionally taurine. I'm considering taking the BCAAs Leucine, Isoleucine and Valine (4:1:1 proportion) for its supposed anti-catabolic effect while dieting. I'm wondering if any of those will have an effect on my mood? I haven't found much information on valine, but understand it can be excitatory.
   I have not tried them to see what effect they have on mood or seen any substantial studies regarding their influence on mood, so I don't know at this time.

Muscle Pharm, BCAA 3:1:2, 240 Capsules
Buy BCAA supplement

BCAA Complex contains branched chain amino acids L-Leucine, L-Isoleucine and L-Valine combined with the conditionally essential amino acid L-Glutamine.  The higher amount of Leucine reflects it's importance in muscle metabolism as an effective branch chain amino acid for stimulation of protein synthesis and it is more readily utilized for energy.  BCAA exert an anticatabolic effect by reducing the breakdown of protein, thereby protecting muscle tissue. Glutamine is a preferred source of fuel for the intestinal cells and is in high demand by skeletal muscles following physical exertion. Vitamin B6 enhances amino acid metabolism. Also consider creatine supplement and powder for muscle tissue size increase.

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Dietary Supplement

L-Leucine
L-Isoluecine
L-Valine
L-Glutamine
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