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  • If you're feeling sleepy and you need a jolt of energy, there's something you should try.

  • It's more effective than drinking coffee or taking a nap.

  • It's drinking coffee and then taking a nap.

  • It's called a coffee nap.

  • It might sound kind of crazy because most people realize that caffeine interferes with sleep.

  • But it takes a little while for the caffeine to affect you.

  • The caffeine has to go into your small intestine, pass into your bloodstream, and enter your brain.

  • That takes about 20 minutes.

  • If you spend those 20 minutes unconscious, you're going to wake up feeling pretty great.

  • And to understand why, it helps to know what's making you feel groggy in the first place.

  • So there's a molecule inside your brain called adenosine and it plugs into little receptors inside your brain cells and makes you feel tired.

  • Adenosine is a by-product of brain activity, so it builds up through the day and starts to slow down your neurons.

  • Caffeine chemically looks a whole lot like adenosine.

  • And when you ingest caffeine and it enters your brain, it blocks adenosine from fitting into those receptors.

  • A lot of people have said that this is like taking a car and putting a block of wood underneath the brake pedals.

  • Caffeine keeps your brain from slowing itself down.

  • The great thing about coffee naps is that sleep naturally clears out adenosine from the brain.

  • So the caffeine doesn't even need to compete with the adenosine to fit into those receptors.

  • So what's the evidence that this really works?

  • There's not a huge body of work but there are a few different studies.

  • When people took a 15-minute coffee nap, they went on to commit fewer errors in a driving simulator than when they only drank coffee or only took a nap.

  • As the test subjects were doing this really boring driving simulation, they were asked every 3 minutes to report their sleepiness level.

  • And the coffee nap group was consistently more alert.

  • Meanwhile, a Japanese study found that people who took a caffeine nap performed a lot better on a series of memory tests.

  • The challenge of the coffee nap is to time it just right.

  • You want to drink it quickly, so it--maybe you could do espresso shots or iced coffee if that makes it easier.

  • And then set an alarm before you fall asleep to wake up within 20 minutes

  • because if you nap too long you're much more likely to enter deeper stages of sleep,

  • and you'll have what scientists call sleep inertia, which is basically grogginess.

  • If you have trouble falling asleep that quickly, the studies found that you can still benefit from the coffee nap.

  • Even just drinking the caffeine and getting a few minutes of restful half-sleep half-awakeness is going to make you feel more alert when you do get up 20 minutes later.

If you're feeling sleepy and you need a jolt of energy, there's something you should try.

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B2 US Vox nap caffeine adenosine brain sleep

Scientists agree: Coffee naps are better than coffee or naps alone

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    Sally Hsu posted on 2018/01/26
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