The A-Z of BCAA

Last updated: Wednesday, August 17, 2005 Print

What is BCAA?
Branched Chain Amino Acids (BCAA) consist of three essential amino acids – leucine, isoleucine and caline. Manufacturers claim better absorption of BCCAs compared to whole (intact) protein found in everyday foods.

How does it work?
Two mechanisms have been suggested to explain the role of BCAA in delaying fatigue. The first theory is that BCAA competes with another amino acid, trytophan, for transport across the blood-brain barrier, so that less trythophan is converted into serotonin. Serotonin is a chemical associated with drowsiness and central or brain fatigue as opposed to muscle fatigue or fuel depletion.

The other theory is based on the fact that as muscle glycogen levels decrease during prolonged exercise, there is an increased oxidation of fat and BCAA as fuel. Therefore free fatty acid (FFA) levels in the blood start to go up, while the availability of BCAA in the blood decreases.

The increase in FFA levels in the blood is accompanied by a release of trytophan from its binding protein (albumin), thus increasing the level of free thrytophan in the blood. Increased levels of thrytophan in the brain promote the formation of serotonin, which is associated with tiredness.

By taking BCAA you can reduce the levels of FFA, which reduces the release of thrytophan from albumin and therefore you have less thrytophan in the blood to promote the formation of serotonin.

Why you might consider using BCAA
Some controlled studies have shown results that may suggest branched chained amino acids play a part in the dampening of protein catabolism. BCAAs are also considered essential amino acids, and are vital in the upkeep of muscle tissue, and may help athletes who participate in high strain physical activities.

What it can do

Activates glutamate dehydrogenase, an important enzyme that is found to be deficient in ALS (amyotrophic lateral sclerosis), and therefore may be helpful for those suffering from Lou Gehrig’s disease
May help in the improvement of mental functions in some exercises that lead to the lowering of brain activity
May assist the upkeep of protein synthesis in muscles at high altitudes, or in extreme temperatures
Intravenous BCAAs may assist in recovery from kidney failure

What it cannot do

Act as a sufficient synthesised replacement for protein food stuffs
Effectively enhance physical performance beyond small increases in fatigue suppression
Help in preventing protein catabolism

Harmful effects
Large quantities of BCAAs are found in everyday food, and so it has been difficult to determine whether a supplementation of these amino acids in excess will have any harmful effects. However, research has shown that ingestion of pure BCAA in large quantities may damage the liver.

p>Who may benefit?

Those partaking in athletic activities at high temperatures or high altitudes
Those suffering from the following: Phenylketonuria, hepatic encephalopathy, tardive dyskinesia, spinocerebellar degeneration, Lou Gehrig’s

Dosage

25 – 65 mg per 2.2 pounds (1 kg) of body weight per day
Athletes following intense training programs should take 2 grams of isoleucine, 4 grams of valine and 5 grams of leucine per day

Legal Status
Legal.

Verdict
There is very little scientific evidence to prove that BCAAs have a positive effect on training athletes fatigue management. The tests that have been done have shown minimal results within controlled test environments. These results cannot be accepted as proof that this is a viable supplement to take. BCAAs occur naturally in foods, and so are not difficult to supplement with a balanced and controlled diet.

(Warren Vonk, Health24.com, July 2005)