Last summer I spent a few weeks in Italy, where the time difference is nine hours from my home in San Francisco. That aggressive time change meant that the first week of my trip was spent pretty exhausted. I survived those first few days on naps and coffee. Then one of the people I was travelling with suggested something interesting: combining the naps and coffee.
Have you ever found yourself chugging coffee to stay up late studying, but then when it's time for the exam, your mind is foggy with fatigue? Researchers from the US Army have developed an algorithm that can predict the energy peaks and valleys that come from drinking caffeine, and in turn, created a web-based tool that helps you predict how alert you can expect to be based on your own sleep schedule and coffee habits.
My Italian friend suggested drinking a few shots of espresso right before I laid down for that power nap. When I woke up later, she said I would feel much more refreshed. She was right.
Turns out, the practice is actually scientifically proven.
While we conventionally think of caffeine as something that prevents us from sleeping, it can be great to have right before that 20-minute nap. In fact, researchers have proven that combining the two leaves you better off than just napping or just having a cup of coffee. It’s a dynamic combo.
The basic idea here is that the way caffeine works, it’s going to take roughly 20 minutes from when you drink it for it to actually give you that jolt you’re after.
Caffeine typically fits into receptors in your brain that are normally filled by adenosine molecules, which are a product of brain activity. You’re tired because those receptors are starting to fill up.
That caffeine you’re drinking has to fight with the adenosine receptors for spots in your brain. However, if you sleep for a bit, you’ll clear some of those receptors out, just in time for the caffeine to come in and grab that prime real estate, Vox reports.
The key here is just taking a short nap of 20 minutes. You don’t even need to fall asleep, a half-sleep stage will help do the trick as well.