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What is muscle protein synthesis and why does it matter for muscle growth?
Muscle protein synthesis (MPS) is the process by which your body builds new muscle proteins. It is the primary driver of muscle growth — when MPS exceeds muscle protein breakdown, net muscle accretion occurs.
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The Science of Muscle Growth
Jeff Nippard · 24 min
Summary
This video explains the mechanisms of muscle protein synthesis (MPS), how leucine and resistance training activate the mTOR pathway, and the practical implications for protein intake timing and dosage to maximise muscle growth.
What is muscle protein synthesis and why does it matter for muscle growth?
Muscle protein synthesis (MPS) is the process by which your body builds new muscle proteins. It is the primary driver of muscle growth — when MPS exceeds muscle protein breakdown, net muscle accretion occurs. Without sufficient MPS stimulation, strength training alone cannot produce meaningful hypertrophy.
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How much protein per meal is needed to maximise MPS, and why is there a ceiling?
Approximately 20-40g of high-quality protein (containing 2-3g of leucine) maximises the acute MPS response per meal. The ceiling exists because mTORC1 saturates — once fully activated, adding more amino acids cannot stimulate further synthesis.
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The Science of Muscle Growth
Jeff Nippard · 4 of 10 saved
Q: What is muscle protein synthesis?
Q: How does leucine activate the mTOR pathway?
Learned 2 days ago
How to Build Good Habits
Ali Abdaal · 6 of 10 saved
Q: What is the habit loop and how does it work?
Q: Why does environment design beat willpower?
Learned 5 days ago
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