Imagine this scenario: You finally go to bed at a decent time and expect to wake up alert and ready to dominate the day. Instead, you find yourself waking up tired after 8 hours of sleep.
According to one expert, you might need more zzz’s if you’re waking up tired after 8 hours of sleep.
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"In order to get a healthy eight hours of sleep, which is the amount that many people need, you need to be in bed for 8.5 hours," sleep scientist Daniel Gartenberg told Quartz. "The standard in the literature is that healthy sleepers spend more than 90 percent of the time in bed asleep, so if you’re in bed for eight hours, a healthy sleeper might actually sleep for only about 7.2 hours."
So chances are good that you’re not actually getting the full number of hours if you’re constantly waking up tired after 8 hours of sleep. You might need to be in bed for at least 8.5 or nine hours to get a full night of rest instead.
What to do if you’re constantly waking up tired after 8 hours of sleep
Some experts say it’s possible to catch up on sleep during the weekends — like if you’re only getting five or six hours of sleep a night, you can sleep in a few extra hours on the weekend to make up for it.
But in order to pay off that sleep debt, it seems like you have to know exactly how many hours of sleep you need a night to function. Gartenberg has a strategy to figure out that number.
"To see how much sleep you really need, my professor suggests that when you go on vacation, try to stick to your normal bedtime and then see what time you wake up," he told Quartz. "With no stressors or time to get up, you’ll just fall into a natural pattern, and that’s probably how much sleep you actually need."
That’s not to say you can’t make up what you lack in sleep if you’re waking up tired after 8 hours of sleep. Small cat naps during the day, like during the energy dip we all experience after eating lunch, can help you get the rest you’re lacking
"A good nap is not a long interruption in the day, but a brief moment of respite, where we’re able to recharge," Dr. Neil Kleine, spokesman for the National Sleep Association, told Forbes "This actually improves our overall activity throughout the day and makes us productive for longer periods of time; it’s the smart move. And if we use that extra energy, we’re still left tired enough to get a full night’s sleep."