Deep sleep refers to slow-wave sleep — a stage in the sleep cycle when brain waves slow down. Getting enough deep sleep is crucial for numerous bodily functions. But how to increase deep sleep isn’t ...

If your mental health has been declining, your sleep-wake cycle may be to blame, according to a new review of literature. Taylor Leamey wrote about all things wellness for CNET, specializing in mental ...

Time to give these so-called sleep hacks a rest? The team behind the sleep tracker Sleep Cycle crunched data from over 1 million global users to determine the social media slumber shortcuts that have ...

Sleeping for 7 to 9 hours at night isn't the only way to catch some z's. Here are four alternative sleep cycles -- and they're pretty obscure. Annie Miller Medical Reviewer Annie Miller is a licensed ...

The internet claims waking at the end of a sleep cycle will leave you refreshed, but experts aren’t convinced. By Clarissa Brincat Published Sep 9, 2025 9:00 AM EDT Add Popular Science (opens in a new ...

How sleeping in 90 minute blocks has helped me get rid of morning grogginess.

Stress and sleep are closely related. Stress raises cortisol levels, delays sleep, reduces sleep quality, and may increase the likelihood of nightmares. A lack of sleep can also affect day-to-day ...

Ever wonder why some mornings you wake up ready to go, and others you feel like a zombie? The difference often comes down to when you wake up during your sleep cycle, and that’s exactly what a sleep ...

Before electricity and endless screen time took over, humans followed a very different rest routine. In the pre-industrial world, people didn’t sleep in one uninterrupted stretch but in two distinct ...