While BCAAs (Leucine, Isoleucine, Valine) can initiate muscle protein synthesis, you need *all* nine essential amino acids for sustained muscle building and repair. A complete protein source (like whey, meat, or a well-designed plant blend) or an EAA supplement provides all necessary building blocks, making them more effective than isolated BCAAs if dietary protein is insufficient or you're training fasted.
Do you use EAAs or BCAAs?"For complete muscle building, aim for all essential amino acids."