No matter what the temperature outside, do you often find yourself putting one foot outside the covers when you're tucked up in bed?
There's a good reason for that.
According to this professor, having one or both feet outside of the bedsheets could promote a better night's sleep.
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The Science of Us spoke to Natalie Dautovitch, a spokesperson for the National Sleep Foundation and a psychology professor at the University of Alabama, to find out more about this sleep hack.
Although there's never been any specific research into this matter, Dautovitch explained the theory is all down to body temperature.
"I think it's likely in service of trying to cool our bodies down because we've gotten too warm to sleep," she said.
Our pre-sleep cooling process plays an important part in the quality of our sleep and the hands and feet in particular are good at this. (Dautovitch explained it's because they're hairless and contain specialised vascular structures to cool the body down.)
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Previous research suggests cooler temperatures cause sleepiness so "sticking your toe out or your foot out could bring you to a more restorative sleep," Dautovitch added.
Even when it's freezing outside, taking off a layer before bedtime might do you a favour.
More to help you get a decent night's shut-eye below: