The human body only uses L amino acids.
Among the most beneficial and effective supplements in any sports nutrition program are branched chain amino acids. These are the essential amino acids leucine, isoleucine, and valine (the three branched-chain amino acids).
Myths debunked ∞
creatine with protein ∞
Myth: "Don't take your creatine with protein because protein contains glutamine and glutamine competes with creatine for the same transporter!"
The Real Deal: There's not an ounce of truth to this. Creatine and glutamine have completely different receptors. Creatine transport into skeletal muscle is regulated by the Creatine Transporter7 while glutamine transport into skeletal muscle is regulated by a system known as "System Nm." 8 The only thing these transporters have in common is that they are both sodium-dependent transporters, meaning that they use differences in sodium concentrations across the cell membrane to drive creatine into cells. Apparently somewhere along the line, somebody believed that since glutamine and creatine transporters both shared that characteristic, they must be the same transporter and the myth spread from there. Let the confusion end here: they do not share the same transporter, and taking protein/glutamine with creatine won't decrease creatine uptake into muscle.