How acute stress affects sleep: large-scale observations from continuous smart ring measurements in free-living conditions.

Stress management may be crucial to improving sleep quality due to the intertwined relationship between stress and sleep. Commercial wearables offer both acute stress tracking and sleep tracking, yet the effects of acute physiological stress on sleep have not been widely studied in uncontrolled, free-living conditions. This study employs stress and sleep data from over 45,000 individuals collected with the Oura Ring during daily life. A group of stressed individuals were compared with a group of individuals with high daytime recovery. Sleep related data were analyzed with respect to the number of accumulated stressful or restorative days, respective to the group in question, within a one-week period. The results highlight the destructive effect that the accumulation of stressful days may have on sleep biometrics, indicating significant decrease in sleep quality. Vice versa, the results also imply the opposite effect from restorative days, emphasizing the importance of balancing acute stress with rest and the potential benefits from data driven stress management.