Research

Hormonal

High work-related stress and increased workload cause a flattened diurnal cortisol pattern (specifically elevated evening levels) and reduced total sleep time, impairing physiological recovery.

If you are experiencing high work stress, expect your sleep to suffer and your stress hormones (cortisol) to remain elevated into the evening. This prevents proper physiological recovery. To mitigate this, you must actively create a buffer between work and sleep (e.g., no work after a specific time) to allow cortisol to drop and sleep duration to recover, as the body does not automatically 'switch off' under high workload.

GoodSupportsHIGH confidence
The results demonstrate that a workweek with a high workload and much stress increases sleepiness and workhours, impairs sleep, and affects the pattern of diurnal cortisol secretion.
Anna Dahlgren et al. · Scandinavian Journal of Work Environment & Health · 2005

Why this rating

Within-person longitudinal design with objective measures (actigraphy, salivary cortisol) reduces selection bias compared to cross-sectional studies, though sample size is modest (n=34).

Source

Different levels of work-related stress and the effects on sleep, fatigue and cortisol

Anna Dahlgren et al. · Scandinavian Journal of Work Environment & Health · 2005

DOI 10.5271/sjweh.883

crossover · n=34Cited 171×
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DOI resolved against Crossref · corpus check 2026-06-10

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