AnswerUpdated May 12, 2026

Can You Sleep During an Ultramarathon?

Yes, but it depends on the format. In a 24-hour race, most runners skip sleep entirely. In 48-hour+ events, sleep becomes mandatory — power naps of 20–30 minutes are the most common approach. In backyard ultras, sleep is possible but must be earned through faster loop times. In 6-day races, most runners sleep 3–5 hours per night in a structured block.

The Short Answer

Sleep strategy is one of the defining differences between multiday formats. The longer the event, the more critical sleep management becomes. Pre-race sleep banking — getting 8–9 hours for 7 nights before the race — significantly reduces cognitive degradation during the event.

Sleep by Race Format

FormatSleep?Typical Approach
24-hour raceUsually noPush through with caffeine, crew support
48-hour raceYes, 1–2 naps20–30 min power nap around hour 28–32
6-day raceYes, nightly3–5 hour sleep block + optional afternoon nap
Backyard ultraPossibleEarn sleep time through faster loops (~45 min)
Stage raceYes, full nights7–8 hours between stages

The Science of Sleep Deprivation in Ultras

After 24+ hours without sleep, cognitive performance drops significantly: decision-making slows, reaction times increase, and perceived exertion rises even at the same pace. But even a 20-minute nap can restore significant cognitive function — what sleep researchers call "sleep inertia recovery." The key is setting an alarm to prevent falling into deep sleep, which causes disorientation upon waking.

Sources

  1. Martin, T. et al. (2018) — "Sleep deprivation in ultramarathon runners." Sleep Medicine Reviews, 42, 130–142.
  2. Poussel, M. et al. (2015) — "Cognitive performance during 24-h running." Journal of Sports Sciences, 33(4), 354–362.

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