Exact time you need to go to bed if you don’t want to feel horrendous in the morning

Picture this: you've set your alarm, you've drifted off to sleep calculating you're going to get your magic eight hours, only to wake up feeling rough as toast every morning no matter what you do.

Even worse if you wake up super disoriented, barely able to recall your own name.

It makes you want to rip your hair out, doesn't it? Especially if you've been trying everything to maximise your shut eye, endlessly scrolling on TikTok to get in on the latest hack to ensure you feel refreshed in the morning.

But the answer might be simpler than you think and it doesn't require any fancy gadgets or lengthy bedtime routines - it's all to do with science.

Basically, once you're asleep your body moves through different sleep cycles.

Each of these cycles are around 90 minutes long - and it's these are the key to unlocking better quality kip, you just need to do a bit of maths.

Dr Karan Raj recently shared a video on TikTok on this topic, advising people on the best time to go to sleep if you want to wake up feeling bright eyed and bushy tailed.

The TikTok doc explained: "Try this if you want to wake up feeling refreshed. Every night your brain moves through several sleep cycles.

"Each cycle starts with light sleep, then you enter deep sleep, then dream, and back to light."

Dr Raj went on to explain that for the most refreshing sleep you want to be waking up at the end of one of those 90-minute cycles when your sleep is at its lightest.

"That’s because you’re closest to your normal waking state and to increase the chances of this, first figure out what time you want to wake up," he explains.

In a nutshell, it's about where in your sleep cycle you wake up, not just the amount of sleep you get overall.

So, how do you actually work it out?

The best thing to do is choose the time you want to wake up and work backwards from that in 90-minute chunks until you find a bedtime that suits you best.

So, if you want to wake up at 8am, your best bet is to hit the sack between 11.00pm and 12.30am to get between seven and eight hours.

Alternatively, if you're a real early bid and want to set your alarm for 6am, you should aim to go to sleep at around 10.30pm.

TikTok users were grateful to finally have some answers over why they still feel so groggy no matter how much sleep they get, with one commenting: "I'm trying this!!"

Another added: "that’s crazy, was wondering why I can have 6 hours or 7.5 hours and feel great. Yet if I have 8-8.5 hours I feel terrible," as a third agreed: "So cool! I'm gonna do that."

Happy sleeping!