Do we sleep less when we travel? New publication in Nature Human Behavior
Professor at DTU and member of the SODAS steering committee Sune Lehmann recently published an article in the prestigious journal Nature Human Behavior, with colleagues from the Technical University Denmark (Sigga Svala Jonasdottir) and University of Vermont (James Bagrow), entitled Sleep during travel balances individual sleep needs.
The authors find that travel has a surprising balancing effect on how much we sleep. In the authors’ own words:
Using a large-scale dataset describing the sleep of wearables users, along with their approximate home location, we studied the typical sleep pattern of individuals at home and away from home. At first, expecting to find that travel generally lowered sleep quantity, to our surprise, we found something more nuanced: for people who usually sleep excessively, yes, less sleep was achieved when traveling. But for people who usually get less than the recommended quantity of sleep, we found that more sleep was had when on the road. In other words, travel tends to have a balancing effect on the quantity of sleep.
Travel is expected to have a deleterious effect on sleep, but an epidemiological-scale understanding of sleep changes associated with travel has been limited by a lack of large-scale data. Our global dataset of ~20,000 individuals and 3.17 million nights (~218,000 travel nights), while focused mainly on short, non-time-zone-crossing trips, reveals that travel has a balancing effect on sleep. Underslept individuals typically sleep more during travel than when at home, while individuals who average more than 7.5 hours of sleep at home typically sleep less when travelling. The difference in travel sleep quantity depends linearly on home sleep quantity and decreases as median sleep duration increases. On average, travel wake time advances to later hours on weekdays but earlier hours on weekends. Our study emphasizes the potential for consumer-grade wearable device data to explore how environment and behaviour affect sleep.