The Claim

In well-trained male cyclists, a 6-day high-fat diet providing 68% of energy from fat is associated with a tendency toward increased activation of the sympathetic nervous system, as reflected by elevated low-frequency power in heart rate variability (P = 0.056), and this effect remains detectable after one day of carbohydrate loading.

Source: Fat adaptation followed by carbohydrate loading compromises high-intensity sprint performance.

What the research says

Supports is higher

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

Supports
50score
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.

Correlation
1 study reviewed
In plain English

If male cyclists eat a super high-fat diet for six days, their body's 'fight or flight' system might get a bit more active — and that change doesn’t go away right after they start eating carbs again.

See the scientific wording

In well-trained male cyclists, a 6-day high-fat diet (68% fat energy) is associated with a tendency toward increased sympathetic nervous system activation, as indicated by a higher low-frequency power component of heart rate variability (P = 0.056), and this effect persists after 1 day of carbohydrate loading.

What the research says

1 study
  1. Study: Fat adaptation followed by carbohydrate loading compromises high-intensity sprint performance.

    The study looked at cyclists who ate a high-fat diet for 6 days and then loaded up on carbs. It found a hint of increased stress on the nervous system, just like the claim says.

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

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