Daylight Savings Time: A Glimpse into the Shiftwork Lifestyle

tired businessman daylight savings
The beginning of Daylight Savings Time has left many of us feeling a bit fatigued. The 6:30 AM alarm instead feels like a 5:30 AM alarm, and even after a few days, lingering fatigue still seems to exist.

Why is it so difficult to adjust to the time change?

Our internal 24-hour clock – known as our circadian rhythm – doesn’t adjust to daylight savings time – even in the weeks following the time change.1 While the 1-hour time change seems minor, the repercussions of this change are dramatic.

Various studies have found that the beginning of daylight savings time is associated with:

  • Increased risk of heart attack 2
  • Increased rate of traffic accidents 3
  • Greater risk of workplace injuries 4
  • Reduced workplace productivity 5

The beginning of daylight savings time reminds us that our circadian rhythms are heavily dependent on our sleep and wakefulness schedules to regulate our alertness, immune response, activity levels, and hormone secretion patterns – along with many other functions.

Shifting Perspectives

Imagine if you had to make drastic changes to your sleep schedule every week. This is the reality of millions of shift workers, athletes, and traveling professionals – many of whom are left with feelings of chronic fatigue due these schedule shifts.

Erratic sleep schedules not only result in fatigue – but can lead to metabolic disturbances and other major health problems. While travel sometimes necessitates dramatic, abrupt changes in our circadian rhythm, shift work doesn’t.

Twenty-four hour operations can implement schedules that better complement circadian physiology – based on the rotational direction of schedules, speed of rotation, and pattern of rotation. To learn more about this – download our FREE white paper on biocompatible shift scheduling.

Biocompatible Shift Scheduling



CIRCADIAN® is the global leader in providing 24/7 workforce performance and safety solutions for businesses that operate around the clock. Through a unique combination of consulting expertise, research and technology, software tools and informative publications, CIRCADIAN helps organizations with traditional and/or extended operating hours optimize employee performance and reduce the inherent risks and costs of sleep deprivation and fatigue.


1. Kantermann, T., Juda, M., Merrow, M., & Roenneberg, T. (2007). The human circadian clock's seasonal adjustment is disrupted by daylight saving time. Current Biology, 17(22), 1996-2000.

2. Janszky, I., & Ljung, R. (2008). Shifts to and from daylight saving time and incidence of myocardial infarction. New England Journal of Medicine, 359(18), 1966-1968.

3. Varughese, J., & Allen, R. P. (2001). Fatal accidents following changes in daylight savings time: the American experience. Sleep medicine, 2(1), 31-36.

4. Christopher M. Barnes, David T. Wagner. Changing to daylight saving time cuts into sleep and increases workplace injuries. Journal of Applied Psychology, 2009; 94 (5): 1305 DOI: 10.1037/a0015320

5. Wagner, D. T., Barnes, C. M., Lim, V. K., & Ferris, D. L. (2012). Lost sleep and cyberloafing: Evidence from the laboratory and a daylight saving time quasi-experiment. Journal of Applied Psychology, 97(5), 1068.


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