As the pandemic spread in 2020 and nations entered lockdown, many people noticed their sleep patterns changing. On social media celebrities started recording bedtime stories to help people fall asleep, while on Twitter #cantsleep was trending regularly.
A year into the pandemic, sleep scientists are beginning to understand how our sleep has changed, and what the implications may be for people’s wellbeing.
Two recent studies tracked sleep patterns of volunteers in Europe and South America in the first months of lockdown. The results told a consistent story: people are sleeping more during lockdown than before it and the timing of their sleep had changed.
Both studies found that lockdown has reduced “social jetlag” – the difference between weekday and weekend bedtimes. Normally, most people go to bed earlier and wake up earlier on weekdays than they would on weekends. Under lockdown, though, sleep patterns make every day look more like the weekend.
Good sleep is not just about quantity, but also quality. Sleep quality takes into account how long it takes to fall asleep, how many times or how easily you wake up during the night, how hard it is to fall back asleep and how refreshed you feel in the morning.
The surprising finding from new studies looking at lockdown sleep is while people are getting more of it, the quality of sleep is worse. A recent UK survey from King’s College London backs up these findings. Half of the UK population said their sleep is more disturbed during lockdown and three in ten said they sleep longer but feel less rested.
It’s not just about feeling tired, there are many possible consequences of declining sleep quality. Good quality sleep is crucial for the body’s immune system to fight off infectious illness. In a landmark study in 2009 researchers monitored 153 volunteers’ sleep patterns for two weeks, and then exposed them to a virus causing the common cold. Participants who had poor quality sleep during the two weeks were six times more likely to develop a cold.
The link between sleep quality and health was bolstered by a large-scale study where 30,000 volunteers provided data on their physical and mental health and sleep patterns over four years. The results showed positive changes in sleep quality over four years were associated with better health and wellbeing.
Good quality sleep not only helps you stay healthy, but also helps your mind stay sharp. In a 2019 study university students at the Massachusetts Institute of Technology were given a Fitbit to wear for one term. The Fitbit recorded their sleep patterns while the researchers tracked their academic performance. Those who slept for longer and got better quality sleep over the month before an exam – not just on the night before an exam – achieved better grades than other students
One explanation for the link between sleep quality and the students’ success could be while sleep strengthens memories formed during the day, poor-quality sleep might jeopardise this process. One study in 2012 demonstrated this by teaching good and bad sleepers to tap a specific sequence of buttons before a night’s sleep and again when they awoke. The good sleepers’ finger tapping skills improved overnight by 15% while the bad sleepers improved by just 1%. Sleep does not benefit learning when the quality is poor.
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From pandemic puppies to late-night online shopping sprees, impulsive behaviour has been a hallmark of lockdowns. While this is partly due to boredom, sleep plays a role too. One study in 2013 investigated decision-making in adolescents, an age group known for impulsive behaviour. Adolescents with poor sleep quality had poorer decision-making skills and made riskier decisions in a gambling game compared to their peers with good-quality sleep.
Get better sleep
The good news is there are effective strategies for improving your sleep quality. A consortium of sleep scientists has published a list of recommendations. These include keeping a regular sleep schedule, avoiding using the bed for activities other than sleep (including Zoom meetings), avoiding electronic devices before bedtime, taking regular exercise and getting as much daylight as possible, especially in the mornings.
Before lockdown, only 44% of UK adults were satisfied with their sleep. For some, lockdown held the promise of more sleep as we were released from the shackles of office hours and a daily commute.
While this dream of more sleep has come true for some, it might not be the kind of sleep they were expecting. Investing in the quality of your sleep is important – you might find yourself smarter and leading a healthier life.
Jakke Tamminen receives funding from the Economic and Social Research Council and The Waterloo Foundation.
Rebecca Crowley does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.