A study published in the journal Sports Medicine – Open provides valuable information about the importance of adequate sleep and sleep management strategies in ultramarathon runners.
Study: Sleep and Ultramarathon: Exploring Patterns, Strategies, and Repercussions of 1,154 Mountain Ultramarathons Finishers. Image Credit: EshanaPhoto / Shutterstock
Background
An adequate quantity of sleep is a prerequisite for optimal physical performance. Sleep deprivation of 24 – 30 hours can reduce reaction time and cognitive performance. An improvement in cognitive and motor performance has been observed in individuals following sleep management strategies.
Besides performance, sleep deprivation can negatively affect recovery after a high-intensity training session. Athletes involved in high-intensity sports, such as offshore sailing and ultramarathon, frequently experience sleep deprivation due to irregular training timing, travel, and extended event duration.
In this study, scientists have investigated sleep patterns and management strategies in ultramarathon runners and assessed the repercussions of sleep deprivation during and after the ultramarathon.
Study design
The study was conducted on 1,154 runners from two ultramarathons: a 165-kilometer race with 9,576 meters of positive elevation and a 111-kilometer race with 6,433 meters of elevation.
The participants were asked to complete a survey questionnaire, which collected information on demographic characteristics, training characteristics, usual sleep profile, circadian typology, and sleep management strategies. The questionnaire was sent to the participants post-race to retrospectively collect the information from the pre-race, during-race, and after-race periods.
The participants were categorized into three groups based on the number of nights they spent during the race: one night, two nights, and three nights. The scientists defined “spending a night in the race” as runners remaining in the race for at least four hours between 6:00 PM and 6:00 AM.
Important observations
About 86% of the study participants were men, and the mean age of the participants was 43 years. The age and gender of the participants were representative of overall race starters. The average finish time was 50 hours for the 165-kilometer race and 34 hours for the 111-kilometer race.
The average daily sleep duration of the participants was 7.5 hours. However, they desired an average sleep duration of 8 hours daily. About 19% of the participants reported having a history of sleep disorder-related symptoms, including insomnia, sleep apnea, and sleep disorder-related depressive syndrome. About 5% reported taking sleeping pills.
About 58% of the participants reported implementing at least one sleep management strategy in preparation for the race. About 18% of the participants reported deliberately experiencing sleep deprivation during their practice sessions for the race.
About 61% of the participants reported modifying their normal sleep patterns one week before the race. Among them, about 55% reported increasing their daily sleep duration, 5% reported modifying their sleep schedule, and 1% reported reducing their daily sleep duration. Moreover, about 46% of the participants reported experiencing one night of partial sleep deprivation during the week before the race.
Most of the participants reported an average total sleep debt of 50 minutes before the race. About 29% of the participants reported having sleep disorder-related symptoms one night before the race. About 13% of the participants reported using sleeping pills or other alternative therapies to get sleep the night before the race.
Sleep during race
About 84% and 53% of the 165-kilometer and 111-kilometer ultramarathon participants reported taking at least one nap during the race, respectively. During the 165-kilometer race, the cumulative sleep duration for each participant was 76 minutes. During the 111-kilometer race, the cumulative sleep duration for each participant was 27 minutes.
A significant correlation was observed between the cumulative sleep duration and finish time in both races. Most participants (82%) reported taking short naps lasting less than 30 minutes during the race. Regarding nap timing, about 80% of participants reported taking naps during the night, whereas only 15% reported taking daytime naps.
Repercussions of sleep deprivation
About 80% of the participants reported experiencing at least one symptom related to sleep deprivation. A variation in symptom prevalence was observed depending on the number of nights spent on the race. The most reported symptoms were reduced alertness and hallucination.
A lower prevalence of sleep deprivation-related falls was observed among participants with increased average daily sleep duration before the race.
Post-race recovery
The participants reported regaining a normal state of wakefulness without drowsiness within two days after the race. About 22% of the participants believed that sleep deprivation during the race increased the risk of accidents in everyday life.
Study significance
The study highlights the importance of sleep management in improving performance and alleviating the adverse health effects of sleep deprivation in ultramarathon runners.
The study finds that increasing daily sleep duration before a race effectively reduces the risk of sleep deprivation-related falls during the race.
The study identifies “short naps” as the most popular sleep management strategy during the race.
New review explores the key gender differences in sleep, circadian rhythms and metabolism