Let's have a show of hands - how many of us have spent an evening winding down, avoiding caffeine and our phones, getting to bed nice and early and still woken up super groggy the next day? Feeling sluggish in the morning is no fun at all, and especially annoying when you can't put your finger on why was your night's sleep wasn't as restorative as you hoped it would be.
Of course, there are all sorts of factors that can play into good sleep, from the right pillows to what you're wearing, but one element that's important to think about, according to a doctor whose TikTok post on the subject went viral, is 90-minute sleep cycles.
Dr Karan Raj is an NHS surgeon who posts handy videos on social media to help us understand the inner workings of our bodies, and he spelled out why it's a good idea to understand sleep cycles.
'Every night your brain moves through several sleep cycles. Each cycle starts with light sleep, then you enter deep sleep, then dream then back to light. Each of these cycles is around 90 minutes,' he explained.
Dr Raj went on to explain that if you wake up at the end of a sleep cycle, rather than setting an alarm for mid-way through one, you'll feel the benefits.
'You’ll feel most refreshed if you wake up at the end of one of these 90-minute cycles. It’s because you’re closest to your normal waking sleep state,' he said.
Working out the optimum time to get up is easy, according to Dr Raj.
'To increase the chances of this, first work out what time you want to wake up – let’s say 8am – work backwards in 90-minute slots until you’re close to the time you want to sleep.
'Try this if you want to wake up feeling refreshed,' he added.
While lots of people might have a vague understanding of sleep cycles, Dr Raj's explanation certainly helps in demystifying this potential blocker of bad sleep. And the best bit? There are smart alarms, wrist trackers and apps that can help you to wake up in alignment with the natural end of a sleep cycle.
It's not the first handy snippet of sleep advice we've gleaned from TikTok of late.
Recently, this runner shared a Could you be an Everesting champ which went viral, as did this Advertisement - Continue Reading Below.
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From: Cosmopolitan UK