The Claim

Three days of refueling with optimal energy availability (52 kcal/kg fat-free mass/day) restores systemic cortisol levels and altered plasma inflammatory proteins to baseline in female endurance athletes after 14 days of low energy availability, but does not reverse exercise performance deficits.

Source: Low energy availability increases immune cell formation of reactive oxygen species and impairs exercise performance in female endurance athletes

What the research says

Supports is higher

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

Supports
71score
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

After 14 days of low energy intake, female endurance athletes who consume 52 kcal per kilogram of fat-free mass per day for three days return to normal levels of cortisol and inflammatory proteins in their blood, but their exercise performance does not improve.

See the scientific wording

Three days of refueling with optimal energy availability (52 kcal/kg fat-free mass/day) restores systemic cortisol levels and altered plasma inflammatory proteins to baseline in female endurance athletes after 14 days of low energy availability, but does not reverse exercise performance deficits.

Why this might work

When the body doesn't get enough energy for a long time, immune cells start producing too much harmful oxidative stress, which damages muscle function and energy production. Even after eating enough again for three days and bringing stress hormones and inflammation back to normal, the oxidative damage in muscles and immune cells doesn't fully repair, so the body still can't perform at its best during exercise.

Verified mechanismbased on 1 study

What the research says

1 study

  1. Study: Low energy availability increases immune cell formation of reactive oxygen species and impairs exercise performance in female endurance athletes

    After two weeks of not eating enough, female athletes' stress hormones and immune signals go back to normal in just three days of eating properly—but their running or cycling performance still stays low. The study proves this exact thing.

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

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