The Claim

Chronic resistance or endurance training modifies the protein synthetic response of functional muscle fractions toward exercise-specific phenotypes without altering the phosphorylation status of Akt–mTOR–p70S6K signaling proteins, indicating that alternative regulatory mechanisms drive these adaptations.

Source: Differential effects of resistance and endurance exercise in the fed state on signalling molecule phosphorylation 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
30score
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.

How it works
1 study reviewed
In plain English

Long-term resistance or endurance training changes how muscle proteins are synthesized in a way that matches the type of exercise performed, but these changes happen without changes in the phosphorylation of Akt–mTOR–p70S6K signaling proteins.

See the scientific wording

Chronic resistance or endurance training modifies the protein synthetic response of functional muscle fractions toward exercise-specific phenotypes, but these changes occur without a corresponding change in the phosphorylation of Akt–mTOR–p70S6K signaling proteins, suggesting that other regulatory mechanisms may drive training adaptations.

Why this might work

When muscles are trained with weights, they make more of the proteins that build muscle fibers; when trained with endurance exercise, they make more of the proteins that power energy production in mitochondria. This happens without always turning up the same molecular switch (Akt-mTOR-p70S6K). Instead, the muscle uses other signals to decide which proteins to build, based on the type of stress it feels — tension from lifting or energy demand from sustained activity.

Verified mechanismbased on 1 study

What the research says

1 study

  1. Study: Differential effects of resistance and endurance exercise in the fed state on signalling molecule phosphorylation and protein synthesis in human muscle

    After training, muscles get better at building only the proteins they need for the type of exercise they do—lifting weights builds muscle fibers, running builds energy factories—but this doesn’t always mean the usual 'on switch' (Akt-mTOR-p70S6K) is changing. So something else must be telling the muscle what to build.

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

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