A weekend lie-in might actually be good for you, according to a new study
- Many of us don't get enough sleep during the week, and then try to make up for it at the weekend with a lie-in.
- Sleep scientists generally don't advise people do this, as sleep is "not like the bank."
- However, a new study has shown that making up for lost sleep at the weekend might not be such a bad idea if you really need it.
It's no secret that unpleasant things happen when we don't get enough sleep. On the surface it can make us more irritable, but it can also have long term affects like an increased risk of dementia.
Unfortunately, many of us don't get the sleep we need due to work, social commitments, or behaviours like binge-watching our favourite shows. This means a lot of us are guilty of the weekend lie-in.
Previous research has revealed how trying to play catch-up with our sleep is a pretty bad idea. Sleep scientist Matthew Walker put it this way:
"Sleep is not like the bank. You can't accumulate a debt and pay it off at a later point in time. If I were to deprive you of sleep an entire night, and then in a subsequent night give you all the sleep you want, you never get back all that you've lost. You will sleep longer, but you will never achieve that full eight-hour repayment. The brain has no capacity to get back that lost sleep."
The odd lie-in might be okay
However, new research contradicts this belief of many sleep scientists, and has shown you might be able to make up for lousy sleep with the odd lie-in. The study from Stockholm University, published in the journal Sleep, looked at the sleeping habits and overall health of 43,000 people.
The results showed that people who slept less than five hours a night, or more than 8 hours a night, had much higher rates of mortality than those who slept more. Overall, it was the average amount of sleep somebody got that seemed to make a difference.
Torbjörn Åkerstedt, a biological psychology professor at the Center for Stress Research at Stockholm University, and lead author of the study, said this seems to show that if you suffer from bad sleep over the week, and make up for it at the weekend, you might be doing your body a favour.
"It seems like you actually can compensate by catching up on sleep during weekends," Åkerstedt said. "This is in effect an argument for lazing around all weekend. There probably is an upper limit, but it's anyway better to increase [sleep hours] on the weekend rather than not doing it at all."
One reason we feel groggy and tired during the week is that we are out of sync with our circadian rhythms, otherwise known as the body clock. If we are on a regular schedule, our hormones make us tired when it's time to go to bed, and wake us up again in the morning.
Work schedules can lead to 'social jetlag'
"The body clock thrives off routine - the more regular you are, the better it is really," Elise Facer-Childs, a doctoral researcher specialising in sleep at the University of Birmingham, told Business Insider when she was interviewed about partners having different body clocks.
She explained something called "social jetlag," which is the misalignment between social and biological time, and how we keep chopping and changing out schedules depending on what day it is.
"A lot of our society suffers from social jetlag because we follow a certain schedule during the week for work, and then we follow a different schedule at the weekend because we're either having a lie in or going out for social activities," she said.
"If you get up at 6 o'clock for work during the week, and then at the weekend you sleep in until 10, that's a four-hour time difference. So for your body, it is like every Friday you jump on a plane and you fly to Dubai, which is a four-hour time zone change, and every Sunday you fly back. That's the sort of social jetlag that's happening to your body, but people just don't see it like that."
Our bodies like routine
It is very easy to stay up too late, or snooze our alarms. Even the slightest adjustment can make us fall out of whack, like when the clocks change in spring and autumn. Making up for lost sleep at the weekends is probably better than doing nothing at all, but the best thing is to keep to a schedule whenever you can.
"There does have to be a balance, because we do get up early during the week, and then that causes an accumulation of sleep debt, so were not sleeping enough during the week," Facer-Childs said. "So it's difficult to get the balance between keeping a regular schedule and catching up on some much needed sleep.
"I'd say the best thing to do is to try and keep a regular schedule, but that means getting up early during the week but not going to bed late."
The new study doesn't recommend always lying in at the weekend, as results also suggested too much sleep can increase the risk of death too. But if you've had a long week, and you really feel like your body could do with the extra rest, don't feel too guilty about it.