CORE MAGAZINE SUMMER 2021

Around the turn of the millennium, Dr. Phillips was one of several
researchers who helped figure out that leucine was the star of the musclebuilding
show, because of its stimulating effect on protein synthesis.1-4
When his and other studies were published, people in the muscle-building
universe got excited.
Their thinking went like this
But hold up, muscle-building universe—don’t get too excited…Do BCAAs
work?
Probably not—for many reasons. Here we go into just three of them.
Reason #1: Leucine can’t build muscle without other
amino acids.
Here’s an analogy: Think of muscle as a brick wall. Granted, this will be an
unusual wall that someone builds and destroys over and over again—but
visualize a wall nonetheless.
When it comes to building that wall, leucine is the most important brick.
The wall doesn’t get built without it.
But leucine can’t finish the job all by itself. You also need histidine bricks,
lysine bricks, methionine bricks, and many other amino acid bricks
If you only have a pile of leucine bricks? No wall.
If you have a pile of leucine, isoleucine, and valine (the BCAAs)? Still no
wall.
You need bricks from all 20 amino acids.
Bottom line: To build muscle, you need all the amino acids, not just
leucine.