The INSIDER Summary:
• The average person needs 7.5 hours of sleep and goes through five sleep cycles per night (the 5th is REM).
• It’s hardest to wake up from sleep cycles three and four.
• If you sleep more than you need to you’re probably going to wake up from a later sleep cycle, meaning you’ll feel groggy and tired even though you’ve slept more.
It’s the weekend and you can’t wait to sleep in; it’s been a long week and a good 10 hours of sleep will do you wonders, right?
According to sleep specialist and author of “The Power of When,” Dr. Michael Breus, more sleep isn’t always better for you.
To understand why this is, we need to look at sleep cycles and how much sleep the average person needs.
Breus says that most people need 7.5 hours of sleep — the revered eight hours is just a myth.
Here’s where that number comes from: The average person goes through five sleep cycles per night. Each one of those cycles is approximately 90 minutes long. Five cycles of 90 minutes each translates to 450 minutes in total which works out to be about 7.5 hours.
However, Breus says that it’s not just the hours of sleep that matter, but also which sleep cycle you wake up from.
“The stage of sleep that you wake up in is the one that has the biggest effect on what I call a sleep hangover,” he says.
There’s stage one, two, three, four, and REM. According to Breus, stages one and two are the easiest to wake up from, REM is slightly more difficult, and then stages three and four are the hardest.
When you sleep an extra hour or two more than you normally do, chances are you’re going to wake up from the REM cycle, or cycles three or four, which means you’re going to feel groggier.
This also explains why taking a short power nap is more effective than taking a longer nap. Longer naps will force you to wake from one of the later sleep cycles, leaving you feeling more tired than rested. Breus recommends napping for just a short 25 minutes instead.
So even if you feel tired enough to sleep forever, stick with the number of hours you need instead.
“If I give people one piece of advice, it’s stick to one sleep schedule, period, end of story,” Breus says. “That will be the most effective in not only helping you fall asleep but to get the good quality sleep you’re looking for.”
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