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Med."],"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Despite proper sleep hygiene being critical to our health, guidelines for improving sleep habits often focus on only a single component, namely, sleep duration. Recent works, however, have brought to light the importance of another aspect of sleep: bedtime regularity, given its ties to cognitive and metabolic health outcomes. To further our understanding of this often-neglected component of sleep, the objective of this work was to investigate the association between bedtime regularity and resting heart rate (RHR): an important biomarker for cardiovascular health. Utilizing Fitbit Charge HRs to measure bedtimes, sleep and RHR, 255,736 nights of data were collected from a cohort of 557 college students. We observed that going to bed even 30\u2009minutes later than one\u2019s normal bedtime was associated with a significantly higher RHR throughout sleep (Coeff +0.18; 95% CI: +0.11, +0.26 bpm), persisting into the following day and converging with one\u2019s normal RHR in the early evening. Bedtimes of at least 1\u2009hour earlier were also associated with significantly higher RHRs throughout sleep; however, they converged with one\u2019s normal rate by the end of the sleep session, not extending into the following day. These observations stress the importance of maintaining proper sleep habits, beyond sleep duration, as high variability in bedtimes may be detrimental to one\u2019s cardiovascular health.<\/jats:p>","DOI":"10.1038\/s41746-020-0250-6","type":"journal-article","created":{"date-parts":[[2020,3,23]],"date-time":"2020-03-23T11:02:43Z","timestamp":1584961363000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":36,"title":["Deviations from normal bedtimes are associated with short-term increases in resting heart rate"],"prefix":"10.1038","volume":"3","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9741-7894","authenticated-orcid":false,"given":"Louis","family":"Faust","sequence":"first","affiliation":[]},{"given":"Keith","family":"Feldman","sequence":"additional","affiliation":[]},{"given":"Stephen M.","family":"Mattingly","sequence":"additional","affiliation":[]},{"given":"David","family":"Hachen","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3932-5956","authenticated-orcid":false,"given":"Nitesh","family":"V. 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