The branched-chain amino acids (BCAAs), leucine, valine and isoleucine, belong to the group of essential amino acids, i.e. those 'building blocks' derived from proteins, which are not produced by our body and which we therefore have to introduce through our diet.
Years ago, it was thought that all three branched-chain amino acids had the same function, but the growing literature has shown that leucine alone is already independently potent in activating protein synthesis, administered in an intake of around 3-4 grams.
Leucine of the three branched-chain amino acids (BCAAs), 'the queen of amino acids' is the main 'key' amino acid involved in muscle protein synthesis capable of directly activating the 'mTOR' enzymatic pathway that stimulates protein synthesis and counteracts muscle catabolism.
Several scientific studies have clearly demonstrated the 'anabolic' effect of leucine, of these, one study in particular (Pasiakos et al,) showed that taking leucine immediately after training increased muscle protein synthesis by around 33%, promoting an insulogenic effect. Yes, because the 'queen of amino acids' not only affects protein synthesis, but also has an effect on improving glucose tolerance and insulin resistance in adipocytes, thanks to increased efficiency and improved insulin signalling and secretion in the pancreas.
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