What are BCAAs and Why is L-Leucine The Most Important?
by Erik Tremblay
BCAAs stand for Branched Chained Amino Acids and consist of three different Amino Acids critical for anabolism (the building of muscle). All three amino acids that make up BCAAs are the only known aminos to be burned by muscles as part of their fuel which is shown by the decline of their plasma and muscle levels during and after strenuous exercise. Check out the importance and role of each of the following BCAAs:
L-Leucine is one of 9 essential amino acids, meaning that it is not produced by the body and therefore must be provided by your diet which is why it is a favorite to supply in our nutritional products. It is one of the three Branched-Chain-Amino - Acids (BCAAs), and is the most important as it has been consistently to shown to have the most powerful effect on stimulating protein synthesis when compared to other amino acids and has the highest concentration in blood plasma and muscular tissue. The most researched pathway is the mTOR pathway, which has been shown to be directly influenced by leucine concentrations. When levels decline, the mTOR pathway is signaled that there is an insufficient amount of fuel available to undergo high levels of protein synthesis, therefore not undergoing anabolic reactions. However, when concentrations of leucine are high, the mTOR pathway is signaled to increase levels of protein synthesis. L-Leucine is the most critical component of BCAAs, which is why we refuse to use ratios that do not heavily favor L-Leucine by atleast 2:1:1(L-Leucine, L-Isoleucine, L-Valine).
L-Isoleucine is one of the 3 BCAAs so it is also an essential amino acid, so it must come from your diet as it cannot be synthesized by the body. Isoleucine also contributes to muscle repair, however it works slightly differently than L-Leucine, as it’s anabolic benefits come its trait of being a precursor to glutamine and alanine which are critical for muscle recovery while also aiding protein synthesis in ways similar to L-Leucine. It is however just as effective in smaller doses and has shown to provide muscle enhancing effects in doses as small as 1 gram!
L-Valine is the third of the BCAAs which acts very similarly to L-Isoleucine as being a precursor to glutamine and alanine. It is also contributed to regulating the central nervous system and improving cognitive function while also providing a basis for cellular repair as an amino acid. The increased benefits of improving the body’s overall function while also contributing to muscle repair is why L-Valine is included in all our BCAA/Pre/Post products.
Since all three amino acids have been shown to decrease in levels over times of strenuous exercise, it is important to dose all three in your regiment. However, Leucine's unique ability to act on the mTOR pathway to either stimulate protein synthesis or inhibit it due to low concentrations is why the doses of Leucine are highly favored in all our formulas. The great part of BCAAs is that your body does not have to break them down before absorption as compared to protein. So while ingesting a complete protein is highly beneficial due to it providing all amino acids, those proteins must be first broken down into the amino acids before they can be absorbed. BCAAs only provide the 3 amino acids listed, but they are the most critical in muscle repair, can be absorbed immediately, and provide sufficient doses instead of smaller doses of aminos with a larger variety.