BCAA (Brach Chain Amino Acid) have been very popular among different kinds of sports athletes who is looking to gain both strength and size.
While EAA(Essential Amino Acids) are a group of nine amino acids that one needs to obtain from the diet, hence the name “essential” , they’re essential because the body is not capable of synthesizing them on its own. In order to synthesize new protein in muscle or anywhere else in the body for that matter, only the EAAs are called L-Leucine, L-Isoleucine and L-Valine, These are also known as the BCAAs due to the shape of their branched carbon side-chain. So, technically, if we take in BCAA, We are in fact also taking in EAA at the same time, just not all of them. Since any given protein consists of (more or less) the full complement of 20 essential and non-essential amino acid, and EAAs need to come from the diet, EAA availability (not BCAA availability) is the limiting factor for muscle protein synthesis at any given time.
All nine EAAs are necessary to build muscle, and research does show that supplementing with these aminos before a workout can support muscle building. However, McMasters University researchers compared the effects of low-dose whey supplements with leucine or EAAs versus complete whey protein. They found that all three could stimulate muscle protein synthesis immediately after exercise, but only the complete whey could sustain MPS for three to five hours afterward
It seems that EAAs bound in food sources are armed with additional nutrients, like immunoglobulins, casein, and glucose, which work to spike insulin levels (an anabolic hormone that stops muscle breakdown and promotes muscle growth), increase energy production, and further support training goals. There’s just more in food than isolated amino acids.