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Visual hallucinations in 246-km mountain ultra-marathoners: An observational study
Ming-Kun Huang1, Kuo-Song Chang2, Wei-Fong Kao3
1Department of Emergency Medicine, Mackay Memorial Hospital; Department of Electronic Engineering, National Taipei University of Technology, Taipei; Department of Medicine, Mackay Medical College, New Taipei City, Taiwan.
The Chinese Journal of Physiology
|October 28, 2021
Summary
Visual hallucinations (VHs) in ultra-marathon runners may stem from extreme physical exertion and sleep deprivation, not altitude or physiological issues. This study explored VHs in a mountain ultra-marathon.
Area of Science:
- Sports Medicine
- Psychiatry
- Physiology
Background:
- Ultra-marathons present extreme physical and psychological challenges.
- Participants in endurance events, like adventure races, frequently report hallucinations.
Purpose of the Study:
- To investigate the occurrence and potential causes of visual hallucinations (VHs) in participants of a mountain ultra-marathon.
Main Methods:
- Thirty-one runners in the 2018 Run Across Taiwan Ultra-Marathon (246 km) were invited to participate.
- Data collected included self-reported questionnaires on sleep, hallucinations, illness symptoms, and the Lake Louise Acute Mountain Sickness (AMS) Score.
- Hematological samples were analyzed pre- and post-race.
Main Results:
- Eight runners were recruited; three (37.5%) reported VHs in the final 60 km.
- All participants slept less than 30 minutes during the race.
- VHs were not linked to AMS, thermoregulatory issues, hypoglycemia, dehydration, or dysnatremia.
Conclusions:
- Visual hallucinations in ultra-marathon runners appear associated with extreme exertion and severe sleep deprivation.
- Factors like altitude, temperature, hydration, and blood sugar levels did not seem to be direct causes in this cohort.
