Researchers from the University of Oulu studied the differences between early birds and night owls to challenge stereotypes associated with each chronotype.

By Hannah C.

“The early bird catches the worm” is an old saying that those who arrive first are most likely to succeed ahead of others, but what about the night owls? Researchers from the University of Oulu studied the differences between early birds and night owls to challenge stereotypes associated with each chronotype.

A person’s chronotype depends on their preferred time of sleep and productivity. For those with an evening chronotype, they’ve typically been associated with low physical activity (PA) and high sedentary time (SED).

The internal clock or circadian rhythm of people vary as some people tend to sleep early while others prefer to work during later hours. It is also commonly thought that we may not have control over our circadian rhythm as some can naturally wake up at dawn without an alarm clock.

Importance of the Internal Body Clock

For the study, 5,156 participants were given wrist-worn accelerometers for two weeks. They also took a modified version of the Morningness-Eveningness Questionnaire to determine their chronotypes.

Results showed that among men, PA and SED were higher for morning chronotypes. For women, there was a higher PA for morning chronotypes while there was no difference between the SED with the female night owls. The researchers also noted that the morning chronotype could be considered in promoting more physical activity.

Our internal clock also controls our mood and appetite. In another study, poor or disrupted sleep was associated with the hormones ghrelin and leptin. Poor sleep quality results in higher levels of ghrelin, or the hunger hormone that enables fat storage after eating. At the same time, leptin levels are decreased, which regulates energy balance and controls the appetite.

Hope For Night Owls

Another factor that could disturb the body’s internal clock is when people live in countries with daylight saving time. Researchers have proposed replacing daylight savings with standard time all-year-round because shifting of a person’s circadian rhythm is harmful to the health, even if it’s just twice a year.

According to sleep experts, the best-case scenario for optimum health is to wake up early, get vitamin D from the early sunlight, and relax more after the sunset. On the other hand, poor sleep quality due to daylight savings has resulted in an increased risk of diabetes, depression, cardiovascular conditions, and brain health.

Knowing our circadian rhythm can help identify the potential health risks we may develop. Since morning chronotypes generally had at least an hour more of activity per day, night owls can slowly incorporate more activity during their days such as taking a walk after meals or short workouts, especially those who work a graveyard shift.

For people that have a day job but tend to sleep late, small modifications in daily habits can have a lasting impact on overall well-being. According to the Sleep Health Foundation, “The good news is that you can re-train your body clock to fit with the times you need to go to sleep and wake up.”

Originally published at science times