Have you ever woken up after a solid eight plus hours in bed and still felt like crap?

Well, a study from the National Sleep Foundation looked at the results from over 277 sleep studies and found that it’s not just the amount of time spent in bed, but other factors like the amount of times you wake up in the night.

They say the key indicators of good sleep are:

• Being asleep for at least 85% of the time you spend in bed
• Taking 30 minutes or less to fall asleep (or up to 60 minutes if you’re 65 or older)
• Not waking up more than once per night for more than five minutes (or twice a night for five minutes for those 65 or older)
• Spending less than 20 minutes awake after initially falling asleep

Sabra Abbott, a neurologist who specializes in sleep disorders, told the Huffington Post that not meeting all four factors does not necessarily mean you’ve had bad sleep. But consistently having problems like finding it hard to fall asleep and waking up a lot could be a sign of an undiagnosed sleep disorder like insomnia or sleep apnea, which are treatable.

• READ: 9 Tips To Have An Amazingly Restful Sleep Tonight

With sleep so important for things like your energy levels, ability to concentrate, and even eating habits, many doctors are saying looking after your sleep health is as important as eating well.

Improving your sleep could mean making simple changes like not using your phone in bed, drinking less coffee, or finding the right position to sleep in.

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