Daylight saving time ends at 2 a.m. local time Sunday, which means you should set your clock back an hour before you go to ...

But the change is slow. Abrupt changes, flying east or west (which extends or shortens sunlight exposure, affecting melatonin ...

This Sunday, we will all dutifully set our clocks back one hour for daylight saving time. But why is our day divided into 24 hours, each hour divided into 60 ...

Neurologist Dr. Ptacek explains how "falling back" disrupts the 24-hour circadian clock, affecting mood and performance, with ...

Here’s what you’ll learn when you read this story: Our biological clock, or circadian rhythm, is immensely important to our health, and scientists are now unpacking the process’s secrets at the ...

If you’ve ever heard someone say a meeting is at 1630 and then felt your brain do a small cartwheel, you have met the 24-hour clock. In the United States, we mostly live by the 12-hour clock, with a.m ...

Armies started using the 24-hour method of timekeeping as standard military time because, much like police, fire, and medical departments, every branch of the armed services is in continuous operation ...

In April of this year, Spanish athlete Beatriz Flamini emerged into the light after a 500-day stay in a cave. Her descent underground is probably the longest undertaken by a long stretch. Flamini says ...

INDIANAPOLIS -- It's known nationwide for rolling back prices. Now Wal-Mart is rolling back something else: its hours. At select locations in markets across the United States, the nation's largest ...