Daily sleep in relation to subjective and physiological stress in an occupational context daily vigor as a mediator

Studies on the stress-sleep relationship consistently demonstrate negative effects of stress on sleep. The reversed relation, however, has received less research attention. Also, field studies on physiological stress are scarce. The aim of this day-level diary study was to examine daily relationships between sleep quality and quantity, and subjective and physiological stress in an occupational context. Moreover, we examined daily vigor as an underlying mechanism of the sleep-stress relationship. Participants were 167 knowledge workers who filled in daily questionnaires measuring sleep quality and quantity, morning vigor and subjective afternoon stress on Tuesdays and Thursdays for five weeks. Physiological stress was assessed with cortisol decline from morning peak to evening, and with blood pressure in the afternoon. Multilevel path analysis results showed that better sleep quality and longer sleep hours predicted increased vigor the following morning, which in turn predicted lower subjective stress in the afternoon. Sleep quality and quantity were not related to physiological stress neither directly nor indirectly via morning vigor. On the basis of our results, sleep should be considered as a factor affecting vigor which in turn seems to lower stress. This article is protected by copyright. All rights reserved.