Sometimes, the difference between a productive day and time wasted can come down to an hour: an hour’s extra sleep, an hour’s exercise, or an hour’s deep work can have a profoundly positive impact on how you work and live.
Almost all of us do it. We get up early to go to the gym. We stay up too late responding to work emails. Or we end up bingeing on Netflix in bed.
Whatever it is, we often cut corners when it comes to sleep.
Yet if you want to kick 2019 off on a stronger, healthier note, you need to make more time for sleep. Because if you can squeeze in even an extra hour, it will almost certainly make you look better, feel better and be better at your job.
But an extra hour should be just the beginning, experts caution. The real benefits of sleep come from setting a personal, optimal sleeping schedule – and sticking to it no matter what.
A person sleeping during the day. But sticking to a consistent sleep schedule at night is the true road to being well-rested, experts say (Credit: Getty Images)
Why skimping matters
It turns out that the benefits of more sleep – and consistent sleep – are diverse and plentiful.
“You’re going to feel better, you’ll have more energy, you’ll have better ideas, you’ll contribute to your team or organisation in a better way,” says Rachel Salas, an associate professor of neurology who specialises in sleep medicine and sleep disorders at Johns Hopkins University in the US.
“Your mood’s going to be better, you’ll have better reason to engage and share ideas,” she says. It will also show on the outside – skimp on sleep and you may find yourself “gaining weight and looking tired with bags under your eyes”.
In 2013, the BBC partnered with the University of Surrey’s Sleep Research Centre for an experiment that found an extra hour of sleep improved participants’ mental agility in computer tests.
But multiple studies make it clear that optimising sleep is about more than tacking on an extra hour. Sleep is crucial, not something to be squeezed in for convenience.
What’s better: an extra hour of sleep or a consistent sleep schedule?
An American study last month showed that students who slept for eight hours a night performed better in final exams. One from the University of Michigan in October found that a lack of sleep affected memory and job performance in fields as varied as baking and surgery.
Another study found that two nights in a row of less than six hours’ sleep could make you sluggish for the next six days. And a Swedish study published this year which looked at over 40,000 participants for 13 years found that those who slept for short periods had higher mortality rates than those who don’t, especially among over-65s.
Most reasonable people already know that more sleep is good for them. The problem is that life – work, children, friends, fitness – often gets in the way. And since they’re able to function on a day-to-day basis, people end up underestimating the power of an extra hour.
Do you drive? A lack of sleep for you could prove deadly. It could result in "microsleeps": sudden episodes of dosing off that lasts just a few seconds (Credit: Getty Images)
So you might get six hours a night – a little less than the UK average – and assume that’s all the sleep you need. But experts say that’s a big mistake. Sometimes, Salas says, people’s bad habits drag on so long they end up with accumulated health issues that eventually bring them to her sleep clinic.
Problems that appear over the long haul could be weight gain, migraines or constant fatigue. It could be sleep apnoea or even what she calls “microsleeps” – when your brain briefly shuts down during the day for just a few seconds, sometimes with your eyes open (an obvious danger to drivers, for example).
But what’s better: an extra hour of sleep or a consistent sleep schedule? Salas says ideally you should do both.
Reut Gruber, an associate professor of psychiatry at Sleep Lab at McGill University in Montreal, says while there is no magic number people should hit, there is a way people can work out how much sleep is right for them.
Schedule everything else so that it allows you to go to bed on time - Reut Gruber
When you’re on holiday or have no commitments the next day, go to bed at a reasonable time and let yourself wake up naturally. Note how many hours you sleep: that number is your new nightly goal. Also note when you fall asleep and when you wake up. Those times are important.
“Once this [number] has been determined, stick to it no matter what,” says Gruber. “Schedule everything else so that it allows you to go to bed on time” and keep on the schedule at which your body naturally woke up.
Humans have internal body clocks that guide when we rest over a 24-hour period. Harmonising your sleep patterns with this schedule is key for real rest (Credit: Getty Images)
That may very well be an extra hour, but for many it could be longer. Experts say many people are sleep deprived and don’t even know it – if you’re sleeping for four hours a night, you’ll probably need the power of many more hours to function normally.
There are caveats, of course: choices during the day inform how well you’ll be able to sleep as you try this out for yourself. That means avoiding excessive coffee or alcohol, which could affect your body’s circadian rhythm – your internal clock that determines when you naturally fall asleep and wake up.
If you can sleep, you need the sleep - Sigrid Veasey
Gruber also says adults should aim for 150 minutes of good old-fashioned aerobic exercise a week to be able to get more rest. “It is a balancing act,” says Gruber. “In order to be healthy, one needs to be active.”
You may be surprised by how long you end up sleeping but, says Sigrid Veasey, a professor of medicine at the University of Pennsylvania’s Center for Sleep and Circadian Neurobiology, “if you can sleep, you need the sleep”. People should “push out the Instagram time” and stick to the schedule, she says.
Salas tried it herself. “I just went to bed at eleven and woke up at seven, even on the weekends,” she says. “No naps. I was going to do it for two weeks. I remember after five days, it was so profound, I remember specifically thinking: ‘Wow, I hadn’t slept this well since middle school’.”
Respect your rhythm
Once you determine your natural sleep schedule, staying on track with that internal clock makes all the difference.
“Even if you get 10 hours of sleep, if it’s not in line with your circadian rhythm, you can actually function like a sleep-deprived person,” says Salas. You can add an extra hour or more, but unless you’re scheduling it to sync with your natural sleep-and-rise times, you might not actually be getting a proper night’s rest.
I remember specifically thinking: ‘Wow, I hadn’t slept this well since middle school’ - Rachel Salas
“People have a very poor sense of judgment on how much sleep they need,” Veasey says. “Until you give yourself extra sleep and you think: ‘I’m flying through the day, getting things done, I’m more interested in people, I’m less moody, I can focus better.’”
If you still feel lethargic after you’ve started getting more sleep, experts say that could be the sign of a more pressing health issue. But improving your sleep is one of those huge health decisions that can give you the biggest “bang for your buck”, Salas says. “It’s one of those things that crosses all medical aspects and domains.”
Setting aside time to work out how much sleep your body needs – and sticking to it – could be one of the best investments you make. Being sharper on the job is great, but being alive is even better.
“People who are sleep deprived are getting into car wrecks. Could you imagine [having a] brain surgeon who’s sleep deprived?” Salas says. “That’s the difference between life and death.”
Bryan Lufkin is BBC Capital’s features writer. Follow him on Twitter @bryan_lufkin.
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