The Scoop on “Night Owls” and Sleep

Night owls are not as motivated to exercise

People who are “night owls” have a tendency to spend more minutes sitting and are less motivated to regularly exercise, according to a new study from researchers in the Behavioral Sleep Medicine Program at the Feinberg School of Medicine at Northwestern University in Chicago, IL.

Glazer Baron provides: “We found that even among healthy, active individuals, sleep timing and circadian preference are related to activity patterns and attitudes toward physical activity. Waking up late and being an evening person were related to more time spent sitting, particularly on weekends and with difficulty making time to exercise.”

A patient’s daily sleeping schedule should be considered when giving exercise advice, especially for less active adults, the study suggests.

Helping your patients understand the importance of sleep and how to achieve it naturally is a critical part of their care.

Being a Night Owl is genetic

All of our body’s processes follow a daily cycle controlled by our circadian clock. A common gene variant that affects virtually the entire population has been found that is responsible for up to an hour a day of our tendencies to be an early bird or night owl.
“The internal ‘biological clock’ regulates many aspects of human biology and behavior, such as preferred sleep times, times of peak cognitive performance, and the timing of many physiological processes. It also influences the timing of acute medical events like stroke and heart attack,” says first author Andrew Lim, MD, who conducted the work as a postdoctoral fellow in the Department of Neurology at Beth Israel Deaconess Medical Center (BIDMC).

“This particular genotype affects the sleep-wake pattern of virtually everyone walking around, and it is a fairly profound effect so that the people who have the A-A genotype wake up about an hour earlier than the people who have the G-G genotype, and the A-Gs wake up almost exactly in the middle,” explains Saper, who is also the James Jackson Putnam Professor of Neurology and Neuroscience at Harvard Medical School.

This same genotype predicted six hours of the variation in the time of death: those with the AA or AG genotype died just before 11 a.m., like most of the population, but those with the GG genotype on average died at just before 6 p.m.

“Also, working out which causes of death are influenced by gene variants like the one we identified may eventually lead to rational timed interventions – such as taking heart medications at particular times depending on which version of the gene variant one carries – to provide protection during an individuals’ period of greatest risk,” says Lim. The potential clinical applications may be as diverse as the many processes that the circadian clock controls.

Women tend to be Early Risers and men tend to be Night Owls.

Night owls report more insomnia symptoms

People who are considered “night owls” tend to report more insomnia symptoms, even though they
 have the opportunity to gain more sleep time, according to a study published in the
Journal of Clinical Sleep Medicine (JCSM).
The study was authored by Jason C. Ong, PhD, and researchers at Stanford University.
It consisted of 312 patients, who were categorized as morning, intermediate and evening chronotypes
based upon scores on the Morningness-Eveningness Composite Scale.
Comparing people with insomnia who prefer evening activities, the “night owls,” to the morning and
intermediate types, the night owls reported the most sleep/wake irregularities and waking distress,
 even after adjusting for severity of sleep disturbance.
“Our findings indicate that further research should investigate the relationship between circadian
rhythms and insomnia, especially with the severity of the ‘night owl’ group,” said Ong.
“These factors may serve to perpetuate the insomnia disorder, and might be particularly important to
 consider when treating this subgroup of insomniacs.”


Best time of day to treat patients and peak

Night owls nervous systems function differently

Researchers at the University of Alberta have found that there are significant differences in the
way our nervous systems function depending on whether we’re early birds or night owls.

Neuroscientists divided the study subjects into two groups: those who wake up early and felt
most productive in the morning, and those who typically felt livelier at night.

Muscle torque and the excitability of pathways through the spinal cord and brain were tested
using magnetic resonance imaging-guided brain stimulation. It was found that morning
people’s brains were most excitable at 9 a.m. This slowly decreased through the day and it
was shifted 12 hours later for evening people, their brains were most excitable at 9 p.m.

Other reported major findings:

  • Evening people became physically stronger throughout the day, but the maximum amount
    of force morning people could produce remained the same.
  • The excitability of reflex pathways that travel through the spinal cord increased over the day
    for both groups.

These findings show that nervous-system functions are different and have implications for
maximizing human performance. This could also influence the optimum time of day for
treatment or adjustment. Are your various patients morning or evening oriented?

These findings were published in the June edition of the Journal of Biological Rhythms.
The research team, included students Alex Tamm, Olle Lagerquist, technician Alex Ley and
neuroscientist Dave Collins.