Why We Should Match Our Work Schedules To Our Biological Clocks

It's not uncommon for shift workers to struggle with the quality of their sleep, often logging less than six hours of shut-eye each night. However, a new study shows that such sleep quality is affected by more than just the timing of your job -- your "early bird" or "night owl" tendencies play a substantial role, too.

A team of researchers from the Institute of Medical Psychology at Ludwig-Maximilian-University in Munich, Germany, recently found that both workers' sleep and general well-being can be improved by employees abiding by work schedules that naturally coincide with their biological clocks. Using a factory as their real-life laboratory and the employees that work there as their subjects, the researchers set out to uncover potential changes that would benefit their sleep, stress levels and overall health. The results of their study were published in the journal Current Biology.

After determining the chronotype of each employee as early, intermediate or late in regards to their natural sleeping patterns, the researchers created a shift scheduling system that took such information into account, pairing workers with shift times at which they felt most awake and alert. The result? They were able to sleep longer and better after their work, and felt less of a need to make up for lost sleep during their time off.

"A 'simple' re-organization of shifts according to chronotype allowed workers to sleep more on workday nights," Till Roenneberg, one of the study's authors, said in a statement. "As a consequence, they were also able to sleep less on their free days due to a decreased need for compensating an accumulating sleep loss. This is a double-win situation."

Employees not only felt more satisfied with their sleep quantity and quality, but also noticed that their "social jetlag," the difference between their desired sleep time and the time actually allowed by their social constructs, decreased by an hour on average. Shift workers tend to be particularly susceptible to the effects of social jetlag, with its effects leading to health problems beyond sleep like obesity and unhealthy habits, such as cigarette smoking and excessive alcohol consumption. Allowing employees to take over shifts that pair with the times of the day they naturally feel most awake and alert could not just help them sleep better, but improve their long-term health as well.

Despite these improvements, the study did document one main drawback: those who prefer to stay up later did not benefit as much from the new shift work schedule as the early or intermediate chronotypes. Roenneberg attributed this lack of change to the fact that just because a person prefers to stay up later doesn't make them truly nocturnal; at the end of day, night work is more demanding on every employee, regardless of sleeping habits.