Leucine
An essential amino acid that directly stimulates muscle protein synthesis.
Updated
Leucine is the most important amino acid for triggering muscle protein synthesis (MPS). It activates the mTOR pathway, the molecular switch for muscle building. Each meal should contain 2.5-3g of leucine to maximally stimulate MPS. This is why protein quality and leucine content matter, not just total protein.
Examples
- 2.5-3g leucine needed to maximize MPS
- 25g whey protein contains ~2.5g leucine
- Triggers mTOR pathway for muscle growth
Related Terms
BCAAs (Branched-Chain Amino Acids)
Three essential amino acids (leucine, isoleucine, valine) important for muscle protein synthesis.
Muscle Protein Synthesis (MPS)
The process by which the body builds new muscle proteins.
Protein
A macronutrient essential for muscle building, repair, and many bodily functions.
Common questions
What is Leucine?
An essential amino acid that directly stimulates muscle protein synthesis. Leucine is the most important amino acid for triggering muscle protein synthesis (MPS).
What are examples of Leucine?
2.5-3g leucine needed to maximize MPS; 25g whey protein contains ~2.5g leucine; Triggers mTOR pathway for muscle growth.
Put it into practice
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