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Performance

Leucine

Also known as: L-Leucine, BCAA component

A
Evidence

Primary amino acid triggering muscle protein synthesis. Can boost lower-protein meals.

Primary uses

  • Muscle protein synthesis trigger
  • Protein quality enhancement

How it works

  • Primary mTOR activator
  • Threshold amount triggers MPS (~2.5-3g)
  • Most anabolic amino acid

Dosage

Typical range
2.5-5g to boost a meal
Timing
With lower-protein meals
With food
With protein-containing meals
Duration
As needed
Special populations
Elderly, low-protein meals, plant-based eaters

Forms

  • Powder
  • Capsule

Safety

Common side effects

  • Bitter taste
  • GI upset

Contraindications

  • MSUD

Known interactions

Evidence notes

Well-established as MPS trigger

Grade A: Multiple well-designed human trials support the main claims.

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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider.