1.BCAAs are especially helpful for maintaining muscle mass while on a calorie-deficit diet.
2. They're particularly useful for bodybuilding competitors who take their physiques to the lean extreme.
BCAAs not only increase the rate of protein synthesis, but they also increase the cell's capacity for protein synthesis.
3. BCAAs also work in your favor by reducing the rate of protein breakdown. They do this (primarily) by decreasing the activity of the components of the protein breakdown pathway, and also by decreasing the expression of several complexes involved in protein breakdown.