mTOR
mTOR (mechanistic target of rapamycin) is the cellular pathway that controls muscle protein synthesis. When you eat enough leucine in a meal (about 2.5 to 3g), mTOR is activated and the cell starts building new muscle protein. Without enough leucine, mTOR stays off.
Why It Matters
Every protein-quality argument ultimately reduces to: which protein activates mTOR fastest and most completely. Whey is the leader in raw mTOR activation because of its high leucine content and fast digestion. Casein activates mTOR more slowly but for longer. Plant proteins need higher absolute doses to reach the leucine threshold.
How to Spot It on a Label
mTOR is not on supplement labels (it is a biology term). But labels brag about high leucine, fast absorption, or 'maximum muscle protein synthesis' as code for mTOR activation. Pre-workout protein products usually highlight this benefit.
Examples from real products
Related Terms
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