Ultramarathon runners exhibited short sleep duration, reduced sleep during competition, and later wake-up times afterward, with nonsignificant trends suggesting increased sleep on pre-race night and greater total sleep time during the post-race week compared with the first post-race night, which may reflect delayed recovery of sleep following the event.
Mean total sleep time during the ultramarathon race was very short at approximately 97 minutes.
Total sleep time during the race was not correlated with race finish time.
Almost all athletes reported symptoms attributed to insufficient sleep during the race.
Athletes had short sleep duration and suboptimal sleep parameters during the pre-race and post-race periods.
Athletes woke up significantly later after the race compared with pre-race timepoints.
There was a nonsignificant trend toward more sleep on the night before the race compared with the prior week.
There was a nonsignificant trend toward greater total sleep time during the post-race week compared with the first night after the race.
The study population consisted of middle-aged male ultramarathon athletes monitored across three distinct race phases using actigraphy.
This research suggests that ultramarathon runners get very little sleep during a race — averaging only about 97 minutes total — and that their sleep is already compromised before the race even begins. Using wrist-worn activity trackers (actigraphs), researchers monitored 13 male athletes participating in the Brazil 135 Ultramarathon (covering either 135 km or 217 km) for a full week before the event, during the race, and for a full week afterward. Even in the days leading up to the race, most athletes slept fewer than 8 hours per night with poor sleep quality, including frequent nighttime awakenings. During the race itself, the sleep deprivation was severe, and nearly all athletes reported symptoms such as excessive sleepiness, loss of balance, or hallucinations. Interestingly, how much sleep an athlete got during the race did not predict how fast they finished, suggesting performance in these extreme events may not be simply dictated by sleep obtained during competition. After the race, athletes tended to wake up later than they had before the event — one of the few statistically significant findings — but the first night of recovery sleep was not dramatically longer than the post-race week average, hinting that sleep recovery may take several days rather than happening all at once. This research suggests that sleep restriction is a pervasive issue for ultramarathon runners, not just during competition but in the days surrounding it. The findings highlight that even dedicated endurance athletes chronically under-sleep, and that extreme events like ultramarathons dramatically worsen this pattern. Understanding how sleep deprivation affects these athletes — and how long recovery takes — could have practical implications for how athletes prepare for and recover from such demanding events.
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Upload Your LabsDaniel N, da Cunha D, Belli T, Esteves A. (2026). Tracking sleep in ultramarathon male runners before, during, and after a mountain race: Actigraphic evidence of sleep restriction.. Sleep health. https://doi.org/10.1016/j.sleh.2026.07.002