Amino acids are known to be the key nutrient for the stimulation of muscle protein synthesis. There are 20 amino acids that are genetically coded in the body. Of these 20, 9 are considered essential amino acids (EAA), because your body cannot synthesize them on its own. They need to come from exogenous sources such as food and supplements. The 9 EAA are leucine, isoleucine, valine, tryptophan, methionine, lysine, phenylalanine, threonine and histidine.

Of these 9, leucine, isoleucine, and valine are called branch-chained amino acids (BCAA) due to their chemical structures resembling branches of a tree. It has been shown in numerous studies that the key amino acid responsible for regulating protein synthesis is leucine.

This happens by leucine stimulating mammalian target of rapamycin or mTOR, which signals the activation of many proteins, including the eukaryotic initiation factor 4E binding protein(4E-BP1) and p70 ribosomal S6 kinase 1 (S6K1). The ribosome is the site in your cells where all

biological protein synthesis, also known as translation, happens. While leucine is certainly needed to initiate protein synthesis, all 9 EAA are critical in building muscle tissue and other proteins, like enzymes.

There have been several studies that show EAA consumption post workout enhances protein synthesis with and without carbs. Adding carbs simply activates the insulin-dependent pathway for protein synthesis via Akt(protein kinase B). However, it has been shown that adding carbs to a mixture of EAA did not increase total muscle protein synthesis compared to just the EAA alone.

Chemix EAA uses specific ratios of EAA based off research showing optimal EAA levels to increase protein synthesis post workout(ratios were designed from a combination of several papers, see references). The leucine dose was increased to meet the leucine threshold, which current data suggested to be between 21-41% of total amino acid concentration (Chemix uses 33% leucine per serving). Studies have demonstrated that the rate muscle protein synthesis can increase up to 291% when your body is in a state of hyperaminoacidemia- when your blood amino acid levels are highly elevated. Therefore, it’s important to consume EAA throughout the day, especially during times surrounding exercise (pre/post/intra).