BCAA

Definition

Branch-chain amino acids (leucine, isoleucine, valine) representing 35% of muscle protein amino acids and directly stimulating protein synthesis.

How it works

BCAAs are essential amino acids that the body cannot synthesize and must come from the diet. Leucine, in particular, activates mTOR, a key protein that triggers muscle protein synthesis. BCAAs are abundant in complete protein foods (meat, fish, eggs, dairy products) and plant-based sources. Supplementing with isolated BCAAs is less necessary if overall protein intake is adequate, but may be useful during fasting or training. The optimal ratio is generally 2:1:1 (leucine:isoleucine:valine).

Role

Stimulating muscle protein synthesis and reducing muscle degradation during intense efforts.

Examples

• Whey protein
• Eggs
• Cheesecake
• Greek yogurt
• Red meat
• BCAA powder
• Peanuts

Recommendations

Ensure adequate overall protein intake before considering isolated BCAA supplementation. If used, take 5-10 g of BCAA before or during a prolonged training session.

Key takeaway

BCAAs are essential to muscle synthesis, better provided by complete protein foods than by isolated supplements.

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