The Claim

During 120 minutes of moderate-intensity cycling at approximately 60% of VO2 peak in healthy young adults, the sensitivity of carnitine palmitoyltransferase I (CPTI) to inhibition by malonyl-CoA is progressively reduced by up to 34% at 10 μM malonyl-CoA, which facilitates increased mitochondrial fatty acid oxidation without changes in CPTI enzyme concentration.

Source: Mitochondrial long chain fatty acid oxidation, fatty acid translocase/CD36 content and carnitine palmitoyltransferase I activity in human skeletal muscle during aerobic exercise

What the research says

Supports is higher

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

Supports
45score
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

During two hours of moderate cycling, the enzyme CPTI becomes less sensitive to inhibition by malonyl-CoA, allowing more fatty acids to enter mitochondria for energy production, even though the amount of CPTI enzyme does not change.

See the scientific wording

During 120 minutes of moderate-intensity cycling at approximately 60% of VO2 peak in healthy young adults, the sensitivity of carnitine palmitoyltransferase I (CPTI) to inhibition by malonyl-CoA is progressively reduced by up to 34% at 10 μM malonyl-CoA, indicating a key regulatory adaptation that facilitates increased mitochondrial fatty acid oxidation independent of changes in CPTI enzyme concentration.

Why this might work

During long periods of steady cycling, muscle cells adjust a key enzyme so it no longer responds as strongly to a chemical that normally blocks fat burning. This allows more fat to enter the energy-producing parts of the cell, where it is burned to make energy, even though the blocking chemical stays at the same level.

Verified mechanismbased on 1 study

What the research says

1 study

  1. Study: Mitochondrial long chain fatty acid oxidation, fatty acid translocase/CD36 content and carnitine palmitoyltransferase I activity in human skeletal muscle during aerobic exercise

    During a long bike ride, the body makes it easier for fat to enter muscle cells to be burned for energy by making a key enzyme (CPTI) less responsive to a chemical that normally shuts it off — even if that chemical stays at the same level.

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

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