COVID-19-mandated social restrictions unveil the impact of social time pressure on sleep and body clock

Maria Korman, Vadim Tkachev, Cátia Reis, Yoko Komada, Shingo Kitamura, Denis Gubin, Vinod Kumar, Till Roenneberg

Research output: Contribution to journalArticlepeer-review


In humans, sleep regulation is tightly linked to social times that assign local time to events, such as school, work, or meals. The impact of these social times, collectively—social time pressure, on sleep has been studied epidemiologically via quantification of the discrepancy between sleep times on workdays and those on work-free days. This discrepancy is known as the social jetlag (SJL). COVID-19-mandated social restrictions (SR) constituted a global intervention by affecting social times worldwide. We launched a Global Chrono Corona Survey (GCCS) that queried sleep–wake times before and during SR (preSR and inSR). 11,431 adults from 40 countries responded between April 4 and May 6, 2020. The final sample consisted of 7517 respondents (68.2% females), who had been 32.7 ± 9.1 (mean ± sd) days under SR. SR led to robust changes: mid-sleep time on workdays and free days was delayed by 50 and 22 min, respectively; sleep duration increased on workdays by 26 min but shortened by 9 min on free days; SJL decreased by ~ 30 min. On workdays inSR, sleep–wake times in most people approached those of their preSR free days. Changes in sleep duration and SJL correlated with inSR-use of alarm clocks and were larger in young adults. The data indicate a massive sleep deficit under pre-pandemic social time pressure, provide insights to the actual sleep need of different age-groups and suggest that tolerable SJL is about 20 min. Relaxed social time pressure promotes more sleep, smaller SJL and reduced use of alarm clocks.

Original languageEnglish
Article number22225
JournalScientific Reports
Issue number1
StatePublished - Dec 2020
Externally publishedYes

Bibliographical note

Funding Information:
This work is supported by Ariel University (M.K.). We thank Elizabeth B. Klerman for her valuable comments on the manuscript. We thank Nebal Egbariah, Mahmud Sindiani, Ashraf Abdo, Rinatia Maaravi-Hesseg, Luisa Piltz, Roumen Kirov, Maria Robles, Vera Vladimirova, Alexander Krivosheev, Ivan Petrov, Tatyana Vasilkova, Svetlana Solovieva and Elena Dergousova for their contributions in translation of the GCCS to different languages and/or for the efforts to advertise the study in different communities. We thank the Portuguese Sleep Society (APS), Japanese Society for Chronobiology (JSC) and Japanese Society of Sleep Research (JSSR) for their help in advertisement.

Publisher Copyright:
© 2020, The Author(s).

ASJC Scopus subject areas

  • General


Dive into the research topics of 'COVID-19-mandated social restrictions unveil the impact of social time pressure on sleep and body clock'. Together they form a unique fingerprint.

Cite this