The Claim

In adult male C57BL/6J mice, REDD1 expression is higher during the dark phase and is suppressed by muscle contraction, and this circadian variation in REDD1 is associated with time-of-day differences in mTORC1 signaling sensitivity.

Source: Time-of-day effect of high-intensity muscle contraction on mTOR signaling and protein synthesis in mice

What the research says

Supports is higher

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

Supports
18score
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

In adult male C57BL/6J mice, REDD1 protein levels rise during the night and decrease when muscles contract, and these daily changes in REDD1 correspond to changes in how sensitive mTORC1 signaling is at different times of day.

See the scientific wording

In adult male C57BL/6J mice, the expression of the mTORC1 inhibitor REDD1 is higher during the dark (active) phase and suppressed by muscle contraction, suggesting that circadian variation in REDD1 may contribute to time-of-day differences in mTORC1 signaling sensitivity.

Why this might work

During the active phase, high levels of the stress-response protein REDD1 block muscle growth signals by turning off a key growth regulator called mTORC1. When the animal rests, REDD1 levels drop, allowing mTORC1 to become more sensitive to signals from muscle activity. Muscle contraction further reduces REDD1, making mTORC1 even more active during rest. This creates a daily rhythm where muscle growth signals are strongest during rest and weakest during activity.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Time-of-day effect of high-intensity muscle contraction on mTOR signaling and protein synthesis in mice

    In mice, a protein that turns off muscle growth signals is more active when they're awake and moving, and less active when they're sleeping — which helps explain why muscle growth signals are stronger during sleep. Exercise reduces this protein, making it easier for muscles to grow.

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

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