BCAAs

Branched-chain amino acids (leucine, isoleucine, valine) get marketed as a muscle-building essential. For most people eating adequate protein (1.6-2.2g/kg/day), they're redundant, because you're already getting them in whey, meat, eggs, and legumes. Where BCAAs might help: fasted training sessions, very low-calorie cuts, or situations where whole-food protein isn't practical mid-session. The evidence for hypertrophy gains beyond what protein intake provides is limited. If your protein is dialed in, skip this.

Also known as: Branched-Chain Amino Acids, Leucine, Isoleucine, Valine