Amino acids Branched-chain amino acids (BCAA) BCAA Powders BCAA(0,4kg)
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The branched-chain amino acids (BCAAs) are leucine, isoleucine, and valine. They make up 35% of your muscle mass. BCAAs are considered essential amino acids because human beings cannot survive unless these amino acids are present in the diet. During intense weight training the body is in a highly catabolic condition. At this time glycogen stores are being rapidly depleted and the liver in turn must synthesize glucose by a conversion of L-Alanine via the glucose-alanine cycle. The BCAA's are involved in maintaining glucose homeostasis through the glucose-alanine cycle. The glucose-alanine cycle involves pyruvate (derived from glucose) being transaminated in muscle to form alanine, with the BCAA serving as the main nitrogen source (donors) for the synthesis of alanine. Then the liver can synthesize glucose by a conversion of L-Alanine. The BCAA's stimulate protein synthesis through insulin secretion/activation of the PI3K pathway, and through activation of mTOR. One pathway through which protein synthesis can be increased is the phosphatodyl-inositol-3-kinase pathway (PI3K). PI3K regulates glucose uptake through GLUT4 translocation and also increases amino acid uptake. Insulin, the body's "storage" hormone, works by activating the PI3K pathway. Interestingly, leucine ingestion causes insulin secretion, but leucine can also directly activate PI3K in the absence insulin. So not only can leucine increase glucose uptake, it can also increase it's own and other amino acids' uptake into cells. The Mammalian Target of Rapamycin (mTOR) is one of the body's protein synthesis regulators. When mTOR is activated (high ATP levels sensed) protein synthesis is increased and when mTOR is suppressed (low ATP levels are sensed) protein synthesis is blunted. Leucine is the key regulator of the mTOR-signaling pathway. Intake of leucine stimulates expression of the hormone leptin in adipocytes. Leptin is a hormone, which is involved in the regulation of metabolism, body weight, and appetite |
