The first time I ever heard about coffee napping was way back when I launched the original design of the “Caffeine: My Drug of Choice” t-shirt you may now recognize. We sold it online in the earliest days of the Internet.
My colleagues and I used to talk about coffee naps a lot, so it’s amazing how so many people still haven’t heard of them today. A lot has happened since then, but coffee naps are still an awesome, under-appreciated way to get a midday energy boost.
I don’t coffee nap often because I rarely nap, period, but when I do, I coffee nap! They’re best for when you’re traveling or jet lagged for a quick burst of rejuvenation.
Coffee Naps 101
Yep, you read that right: two of the most Bulletproof things, sleep and coffee, go hand in hand to boost your performance when you use them together correctly.
Drinking a cup of coffee followed by a 20-minute rest can give you an effective siesta that fuels your afternoon. Some call it a coffee nap; we call it a Bulletproof Power Nap.
Sound crazy or even counter-intuitive? After all, we drink caffeine for alertness, not to sleep. Here’s how it works and the science behind it.
Coffee Naps: Powered By Science
A quick coffee nap is an incredible way to boost energy and productivity during your day because of what goes on in your brain as it’s happening.
When you drink caffeine, it passes to your small intestine and gets absorbed into your bloodstream. It then kickstarts your brain chemistry by blocking receptors normally filled by similar energy transferring molecules of Adenosine, a chemical compound in your brain known for causing drowsiness.
Adenosine makes you feel sleepy by slowing down your brain’s nerve cell activity; so when caffeine binds to your receptors instead of Adenosine, the reverse happens.
When caffeine takes Adenosine’s place in the receptors, it has the opposite effect; the nerve cells speed up giving us that jolt of caffeine energy and focus. 
So, what does any of that have to do with a 20-minute power nap? The brilliance of the coffee nap is that sleep naturally clears Adenosine from your brain. From the moment you drink your coffee to the moment you metabolize it is about 20 minutes of pure opportunity to not only rest, but to open up those Adenosine receptors to the caffeine you just imbibed. 
It’s like rolling out a welcome mat just for your coffee. What could be better?
What Kind of Nap Works? What If I’m Not Good At Napping?
You don’t have to fall into a deep sleep for a coffee nap to work. Half-sleep or “nonsleep dozing” has proven to be just as effective. 
It’s important not to sleep any longer than 20 minutes as you can fall into sleep inertia, which is harder to wake from. You also need to be awake when that caffeine reaches your brain. 
Why Do Coffee Naps Work So Well?
In several UK studies, researchers found that when subjects took a 15 minute coffee nap, they scored higher on a driving simulator test.
The coffee nap formula is pretty straightforward. Find a quite corner at work or home, and give it a try. Maybe even explain it to your boss, so they know you’re upgrading your brain and your productivity.
Dave Asprey, founder of Bulletproof and creator of Bulletproof Coffee, is a Silicon Valley tech entrepreneur who spent 15 years and $300,000 to hack his own biology, lose 100 pounds, upgrade his IQ, and lower his biological age. You can find more about biohacking, the art of changing your environment and your biology so you perform better, on the bulletproofexec.com blog.
This post originally appeared on the Bulletproof blog.