University took my circadian rhythm and shot it between the eyes

… but napping is keeping it on life support.

As a university student, EMT, and someone who has worked in technical theatre professionally for almost 10 years, I am intimately familiar with exhaustion and sleep deprivation. I share with those who may stumble across this, my intimate knowledge of napping.

Napping is awesome for increasing your alertness, productivity, and cognitive function. It combats sleepiness, which can be hazardous when providing patient care or operating a vehicle. If you’re a student, it can also be hazardous to your grades.

1 – Introduction

The most important aspect of a nap is the duration. Secondarily, there are a some adjuncts you can use to increase the quality of your sleep.

The figure above is your sleep cycle. You can see that you go from being awake, to deep sleep, back to nearly waking, over and over until you awake (ideally) from a “shallow” REM sleep.

Ever wake up and just can’t seem to get moving? That’s called sleep inertia, and it’s normally caused by a disagreement with your sleep cycle. You most likely woke up in deep instead of shallower sleep, so your body wasn’t ready to wake up. If you had slept a little less or a little more, you would have been fine.

It’s not very clear from the graphic above, but an average person’s sleep cycle is around 90 minutes. Meaning, you go from waking, to deep sleep, nearly back to waking in an hour and a half. After you go to sleep, you really start to plummet into deep sleep after 20-30 minutes, and you won’t be near waking again until the end of the 90 minute cycle.

2 – Duration

Understanding your sleep cycle is the key to getting an energising nap. Since we want to wake up from a shallow sleep in order to avoid sleep inertia, our naps need to less than 30 minutes or at least 90.  You may need to tweak these times based on how your personal sleep cycle exactly works. If you’ve spent any time studying anatomy or physiology, you know that everybody is a little different. I can’t stress enough that this is the biggest part of getting naps right – the duration.

3 – Adjuncts

Sometimes we can use adjuncts to increase the quality of our nap and help us get to sleep faster.

A. Sleep Mask

Photo Credit

You will never realise how much ambient light kept you from getting to sleep until you try using a sleep mask. Since you, as a medical professional, will likely be seeking napping bliss at all hours, these can he a huge help. Sleep masks have some different qualities or features you should be aware of when purchasing. Expect to spend around $20 for a decent one.
Material – Masks come in nylon and cotton. Many people prefer the cotton or cloth-like materials. Consider going to a store and feeling a couple to decide what you prefer.
Light Blocking – You would think that all sleep masks are 100% like blocking, but they aren’t. Cheap nylon ones allow some light through and will annoy you. Most quality sleep masks that you will find for purchase will block all light. It’s normally the cheap complimentary ones you get that will leak.
Padding – Nicer sleep masks will feature padding in the periorbital region to keep the mask from laying completely against your eyes, as this can be annoying.
Ear plug storage – if you choose to use earplugs, it can be convenient to store them in your sleep mask.
B. Ear Plugs

This might sound familiar, but you won’t realise how much ambient noise was distracting you from sleep until you use earplugs. There are a couple things to consider when purchasing earplugs. You should only need to spend, at most, a couple dollars on a pair of earplugs.
Noise Reduction Rating – All earplugs are given a noise reduction rating in dBNR (decibels of noise reduction) that is the number of decibels the earplugs reduce ambient sound when worn correctly. The decibel scale is logarithmic and was modelled after the sensitivity of human hearing. Every 10 dB is factor of two (twice/half as loud), so earplugs with a 20dBNR rating would only allow 1/4 of the ambient sound into your ears.
Material/Construction – Most of the earplugs you’ve ever seen are probably the foam kind you’re meant to squish and roll up to place in the external auditory meatus. These can be very comfortable, but are easily worn incorrectly. When it comes to disposable earplugs, I prefer the triple flanged rubber type pictured above.
If you’re serious about earplugs for occupational reasons (or whatever), you can see an audiologist and order custom fitted earplugs. I’ve had great success with EAR Inc. If you go the custom route, you can easily spend $100 or more for fitted “musician” earplugs. However, you’ll only want simple solid silicone molds for napping. These will cost considerably less, probably only $40 total, but I’m not completely sure as I’ve only ever ordered the musician type.
C. Caffeine

You might be thinking, “how on earth can caffeine helper rather than hinder a nap?” We all know that after it’s ingested, caffeine will take some time to actually be absorbed and have any effect. Luckily this happens to be around the same length of time our short nap will be. So, if you quickly drink some caffeine, then take a 20-30 minute nap, when coming out of it you will have the combined benefits of the sleep and the caffeine. Caffeinated power naps are awesome.
4 – Conclusion / Summary

Naps are amazing. Use them. Sleep less than 30 minutes. If you need to sleep more, then go for at least 90. Use a sleep mask and earplugs to improve how quickly you fall asleep. Pound some caffeine right before a 20-30 minute nap for an extra pick me up.
Lather, Rinse, Repeat.
Mat Goebel
Research Fellow

My research interests include EMS, EKG, STEMI, cybersecurity, data viz, ML, and NLP.