Extreme running may temporarily weaken immune system, study suggests

NCT ID NCT06089174

First seen Jun 27, 2026 · Last updated Jun 27, 2026

Summary

This study looked at whether running an ultratrail (a very long race) raises the risk of getting an infection afterward. Researchers followed 471 runners and their companions, asking about symptoms like fever, sore throat, and fatigue for three weeks after the race. The goal was to see if the immune system's temporary dip after extreme exercise leads to more infections.

What this could mean

Our plain-language read of the trial. This is informational only — not medical advice or a prediction.

What this could lead to
If confirmed, this could help runners and doctors better understand when to watch for infections after extreme races.
What could go wrong
This is an observational study, not a treatment trial. It cannot prove cause and effect, only suggest a link.

This is an AI summary of the original study and may miss details. Read our disclaimer.

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Conditions

The condition(s) this trial relates to.

As listed by the trial registrant

The condition terms exactly as the trial's registrant entered them.

Contacts and locations

Locations

  • CHU Réunion

    Saint-Denis, 97400, Reunion

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