(Healthline) – Before going to bed tonight, many Americans will be setting their clocks back by an hour.
Daylight saving time officially comes to end at 2:00 a.m. on Sunday, Nov. 3, when standard time begins.
You might be looking forward to getting an extra hour of sleep that night, but the amount of rest that you get will depend in part on your sleep habits.
If you’re the sort of person who doesn’t wake up until your alarm clock rings, you might get some extra rest, but only if you go to bed at your normal hour.
“If you actually went to bed at your usual time and took advantage of it, yes, you possibly could get an extra hour of sleep,” Dr. Fariha Abbasi-Feinberg, FAASM, FAAN, the director of sleep medicine at Millennium Physician Group in Fort Myers, Florida, and a member of the board of directors of the American Academy of Sleep Medicine (AASM), told Healthline.
“If you actually got that extra hour of sleep, that could be greatly beneficial,” she continued, “but unfortunately, most people do not take advantage of that extra hour and instead decide to stay up and socialize or do other things.”
You might also get less than an extra hour of sleep if you’re a morning person who tends to wake up on your own, without an alarm. That’s because it can take several days or more for your body’s internal clock to adjust to the change.
“Those folks who tend to wake up before their alarm [goes off] will actually wake up and discover that, ‘Wow, I have a whole other hour until I need to go to work,’” Erik Herzog, PhD, a professor of biology and neuroscience at Washington University in St. Louis and president of the Society for Research on Biological Rhythms, said.
“Because if you think about it, there’s nothing that’s really changing in the environment. The sun is still coming up, the Earth is still rotating around its axis in the same way, and the only thing that’s changed is the clock on the wall,” he added.
Changing road conditions
After you roll your clock back, you might notice that the skies are lighter when you leave your home in the morning. On the other hand, the sun will set an hour earlier in the evening.
That could potentially affect the risk of traffic accidents, as drivers adjust to the change in light levels and visibility.
When scientists reviewed the research on traffic accidents following the autumn time change, they found conflicting results: a third of studies found that traffic accidents and injuries increased after the change, a third found that accidents and injuries decreased, and a third found no significant difference.
Some of the studies in the review found that pedestrians were more likely than motorists to be injured in traffic accidents after the return to standard time.
That might reflect the fact that pedestrians tend to spend more time outside in the evenings, which get darker an hour earlier after time change.
On the other hand, drivers who get extra sleep when they roll their clocks back may be more alert on the roads. This might help account for the fact that some studies have found that traffic accidents and injuries decline following the autumn time shift.