The Vicious Circle of Working Hours, Sleep, and Recovery in Expert Work.

This study aimed to investigate working hours, sleep quality and alertness, and recovery and detachment in expert work using a mobile app. The study sample comprised members of The Finnish Business School Graduates and employees of an information technology (IT) company. The final study sample included 154 employees with at least four days of mobile app data. For statistical analyses of the survey and mobile app data (cross-sectional setting), we used logistic regression, and for the day-to-day data, we used multi-level logistic regression to calculate the odds ratios (OR), and a general equation estimates model for regression coefficients with 95% confidence intervals (CI). The results showed that moderate to fair sleep quality or alertness at awakening were associated with longer working hours the following day (OR 1.07⁻1.14, 95% CI 1.01⁻1.22). Recovery and detachment during the preceding day were associated with longer working hours. These associations were the same in the opposite direction. To conclude, the day-to-day ratings of sleep quality and alertness at awakening, and recovery and detachment from work during leisure time were associated with increased working hours the following day. In addition, longer working hours the preceding day were associated with worse ratings of sleep quality, alertness, recovery, and detachment.