Martínez Madrid warns that even brief exposure to light at night can fragment sleep and increase cardiovascular risks.

Feeling tired despite enough hours? Learn how understanding your 90-minute sleep cycles & using a sleep calculator can help ...

While these tools are helpful, they take a long time to calculate ... they track sleep metrics as well. Not only will they track your sleep cycles, but using the sensors to detect sleep, they ...

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 ...

The key to getting good sleep is understanding how it works. But it's a complicated thing. And, while we usually hyperfocus on sleep duration, counting the hours of rest we get and assuming the ...

It's common to describe getting a good night's rest by saying we've had a really deep sleep. But in reality, actual deep sleep is just a portion of the 7 to 9 hours sleep that's recommended for ...

You are able to see recommended times for you to wake up according to your current time, or calculate the best time for you to fall asleep by choosing a certain time you'd like to wake up in the ...

The Sleep Charity organization's website explains that sleep cycles are about 90 minutes each. So if you calculate backwards, you will be able to know when to go to sleep and when to wake up. For ...

An irregular sleep-wake cycle is associated with a heightened risk of major cardiovascular ... They wore an activity tracker for 7 days to record their sleep, the data from which were used to ...

An irregular sleep-wake cycle is associated with a heightened ... the data from which were used to calculate each person's Sleep Regularity Index (SRI) score. People with an SRI score of more ...

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 ...