The Claim

Ingesting a leucine-enriched essential amino acid and carbohydrate solution one hour after resistance exercise in young, untrained men increases muscle protein synthesis by 145% above baseline, compared to a 41% increase with exercise alone, likely due to enhanced phosphorylation of mTOR, S6K1, and 4E-BP1 signaling proteins.

Source: Leucine-enriched essential amino acid and carbohydrate ingestion following resistance exercise enhances mTOR signaling and protein synthesis in human muscle.

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
46score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Cause and effect
1 study reviewed
In plain English

If young men who don’t usually lift weights drink a special protein-and-sugar shake one hour after working out, their muscles build protein much faster—nearly triple the rate—than if they just worked out alone, probably because the shake turns on key muscle-building signals in their cells.

See the scientific wording

Ingesting a leucine-enriched essential amino acid and carbohydrate solution one hour after resistance exercise in young, untrained men increases muscle protein synthesis by 145% above baseline, compared to a 41% increase with exercise alone, likely due to enhanced phosphorylation of mTOR, S6K1, and 4E-BP1 signaling proteins.

Why this might work

After a workout, drinking a shake with leucine and sugar causes leucine to enter muscle cells and turn on a growth signal called mTOR, while the sugar triggers insulin release, which also boosts this signal. Together, they fully activate mTOR, which then switches on two key proteins that help build new muscle proteins: one frees the starting switch for protein production, and the other helps the cell make more of the machinery needed to build proteins. This leads to a big increase in how fast muscle proteins are made.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Leucine-enriched essential amino acid and carbohydrate ingestion following resistance exercise enhances mTOR signaling and protein synthesis in human muscle.

    When young men who don’t usually lift weights drink a protein-and-sugar shake an hour after working out, their muscles build protein much faster than if they just worked out alone — and this happens because the shake turns on key cellular signals that tell muscles to grow.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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