I know, it seems counter intuitive. But new evidence is showing that maybe having a quick cup of coffee right BEFORE a nap may actually help you to wake up feeling more refreshed, and ready to tackle the rest of the day. In fact, scientists are now pretty much in consensus that it will actually have more benefits than a plain ole’ nap. But what is the science behind it and does this have any merit?
We can’t understand how a coffee nap can be so effective without first understanding a neurochemical called adenosine. Adenosine is naturally occurring throughout nature and is believed to play a role in the way our body manages our sleep cycle by promoting sleep and supressing many of the processes we associate with wakefulness. It slowly builds up in your brain throughout your waking hours in a process described as, “accumulating sleep debt.”; this is a natural product of your body using up your energy stores at a cellular level. The more adenosine you build up, the heavier your eyes get, and the less alert you become.
Experiments have shown that animals forced to stay awake past typical ranges show a large spike in adenosine levels. Similarly, animals injected with adenosine seemed to fall into natural sleep cycles shortly afterwards. All this indicates that sleep and adenosine buildup play some role in replenishing our energy stores when they have become depleted; possibly by switching out the outgoing adenosine for energy rich glycogen.
But what does any of this have to do with Coffee? Well, by some divine coincidence it seems that caffeine has a structure that is very similar to adenosine. I like to think of them as similar puzzle pieces while your brain is the larger puzzle; as the adenosine molecules build up along the puzzle, you become more and more tired. Enter Caffeine. Caffeine fits those adenosine slots perfectly! So perfectly in fact that it leaves no room for adenosine to slot in.
A quick sidebar to discuss the actual mechanism by which caffeine manages to keep us awake. It actually has nothing to do with waking you up, but rather should be thought of as stopping you from getting more tired. As you fill your brain with Caffeine it takes up all of the empty slots that would otherwise be filled with adenosine. Since it has nowhere to go, the adenosine can not build up on the receptors and as such, you will not get sleepier. There is a downside though, caffeine can only prevent adenosine from entering an otherwise empty slot, it cannot force adenosine out of a spot it’s already claimed. This is why your morning coffee always seems to be so much more effective when compared to your 2:30, afternoon slump coffee. Unfortunately, the only way to clear out some of that sleep debt, is to sleep.
Enter, the coffee nap. The coffee nap is devilishly clever in it’s efficiency and exploits this loophole in physiology. The thinking goes like this, as adenosine builds up you become more and more groggy. Seeing that you won’t survive the rest of the afternoon, you make the decision that you will go take a nap but first, you go drink a big cup of coffee as fast you can. Once inside you, your body starts to process the coffee as you quickly nod off. Set your alarm for roughly 20 minutes later as 20 minutes seems to be the ideal nap time, both coffee or otherwise. If you sleep longer than 20 minutes you risk experiencing something scientists call “sleep inertia” which will leave you feeling groggy for 20 minutes to an hour after waking.
If you’ve timed everything correctly, you should be waking up just as the caffeine is reaching your brain, a brain, which has recently been cleared of all it’s sleep debt. Since the adenosine receptors are all free, caffeine swoops in claiming all the available spots! This leave no room for adenosine to build up and leaves you feeling refreshed for much longer than a simple nap ever could have. Remember, the nap would only have eliminated the adenosine which would have started building up immediately upon waking. With the coffee nap however, the adenosine has nowhere to slot in until 1 to 2 hours later when the caffeine relinquishes its spot.
So there you have it! The secret to a more productive afternoon is the coffee nap! If only we could get our bosses to buy into the concept…