Bedtime regularity is emerging as a key factor in improving sleep quality. We came across this recent study published by Nature that set out to establish the association between bedtime regularity and resting heart rate (RHR) as an important biomarker for cardiovascular health.
After looking at data from 255,736 nights of sleep collected from a cohort of 557 college students, researchers found that going to sleep even 30 mins later than your normal time was
“associated with a significantly higher (+18%) resting heart rate (RHR) throughout sleep. This higher RHR persisted into the following day.”Faust, L., Feldman, K., Mattingly, S.M. et al. Deviations from normal bedtimes are associated with short-term increases in resting heart rate. npj Digit. Med. 3, 39 (2020)
Interestingly, a higher RHR was also observed in individuals who went to sleep too early!
A Higher RHR has been established to be associated with an increased risk of all-cause and cardiovascular mortality in a broad number of research studies. Now we have a clue on how to improve our health outcomes: stick to a consistent bedtime.
Connecting dots: this study is consistent with what the folks at Oura have discovered having analyzed the sleep results of their over 150K customers.