Estimates suggest that over 80% of all adults in the United States drink coffee; this equates to roughly 4/5 adults. There are many benefits associated with caffeine intake, and even more specifically linked to coffee consumption (e.g. reduced risk of certain cancers). The caffeine content within coffee is used by the masses as a means to overcome morning grogginess and improve cognitive function.
The stimulatory effect resulting from caffeine intake is even thought to temporarily increase IQ. Although cognitive stimulation via the caffeine in coffee is one way to improve your performance and boost your energy levels, another tactic of performance enhancement is that of napping. While midday sluggishness is often mitigated with an extra cup of coffee, napping provides benefits that coffee cannot.
Napping helps the brain restore itself, form new connections, and aids in the process of learning. The science supports the idea that naps at work can improve performance for the rest of the day. Clearly there are mental benefits associated with coffee (and its caffeine) as well as napping, which has resulted in the combining of the two practices in the form of a “coffee nap.”
What is a coffee nap (or caffeine nap)?
A coffee nap is defined as a short nap (i.e. light sleep period) taken immediately after the consumption of caffeine. The idea behind it is that consuming caffeine just prior to taking a short snooze aids in the restoration of alertness and brain function. In fact, adding caffeine to the equation of napping is thought to provide superior restoration to brain function than solely just taking a power nap.
Most coffee naps last between 10 and 20 minutes and are taken during the afternoon, but the effect should be similar regardless of the time of day. The vigilance, alertness, and cognitive enhancement as a result of caffeine consumption is thought to peak approximately 30 minutes after consumption. If you drink coffee prior to taking a nap, you end up reducing caffeine’s competition for adenosine receptors.
Adenosine is considered an endogenous chemical compound that regulates an array of physiological processes, one of which is sleep. As more adenosine binds to adenosine receptors, it slows down nerve cell activity and we feel sluggish or sleepy. The longer you’ve been awake, the greater accumulation of adenosine you have within the brain, leading to tiredness.
After sleeping, even for a short duration (e.g. napping), the amount of adenosine in the brain is significantly reduced, leading to greater feelings of alertness. Like adenosine, caffeine also binds to adenosine receptors, however it is considered an “antagonist” in that it nerve cell activity isn’t slowed, rather it actually speeds up – leading to feelings of alertness.
Since napping depletes the build-up of adenosine, and caffeine competes with adenosine for the “adenosine receptors,” drinking caffeine prior to napping gives coffee free reign over these receptors – there’s reduced competition. Scientifically, this leads to a greater cognitive enhancement than solely drinking coffee without taking a nap.
- Source: http://www.ncbi.nlm.nih.gov/pubmed/20164566
- Source: http://www.ncbi.nlm.nih.gov/pubmed/9401427
Scientific Benefits of Coffee Naps
There is clear scientific evidence to support the idea that “coffee naps” provide superior increases to mental performance and alertness than either method as a standalone option. Therefore those who take “coffee naps” may be getting the best of both worlds in regards to the adenosine antagonism of caffeine, and the adenosine reducing effect of the nap.
Best of both worlds: For people that like taking naps and drinking coffee, this is the ultimate way to pack a potent punch of alertness and vigilance. Many people engage in morning coffee drinking, and some of those same people likely take an occasional nap. Others may continue drinking coffee well into the afternoon without considering a nap.
By drinking some coffee prior to napping, you’re setting yourself up to get the “best of both worlds.” Take the beneficial effects of caffeine and amplify them with a nap. The science supports this idea, so it may be something to consider.
Combating sleep inertia: Sleep inertia is characterized by reductions in motor dexterity and subjectively reports of grogginess after an abrupt awakening. Those with severe sleep inertia feel sluggish and as if their alertness is compromised for an extended period after sleeping. While napping for just 20 minutes isn’t usually associated with grogginess, prolonged naps (e.g. over 30 minutes) are.
This is due to the fact that a person enters a deeper stage of sleep, and if abruptly awoken from that sleeping state, their brain waves are still slow (e.g. theta waves). Although shorter naps aren’t associated with severe sleep inertia, it is possible for sleep inertia to occur regardless of the nap duration. Fortunately by adding caffeine to the equation (from coffee), the effects of sleep inertia (e.g. grogginess) are mitigated.
Therefore you’re much less likely to feel sluggish upon waking if you take a coffee nap over a standard nap. A study from 2001 analyzed the effects of caffeine on sleep inertia in 28 participants. Results recorded that caffeine’s antagonism of adenosine receptors successfully combated all evidence of sleep inertia.
- Source: http://www.ncbi.nlm.nih.gov/pubmed/11683484
Enhanced effect of caffeine: As was already mentioned, the effect of the caffeine content in coffee becomes enhanced as a result of napping. When you take a short siesta, the levels of adenosine are reduced. Since caffeine competes with adenosine for “binding” neural real estate (i.e. adenosine receptors), there ends up being less competition for the caffeine.
This leads to more caffeine molecules binding to the adenosine receptor sites as antagonists. The antagonist effect from the caffeine molecules leads to a speeding up of nerve cells and ultimately increased alertness than you’d get from drinking caffeine without a nap.
Synergistic effect: Most evidence suggests that the benefits of a caffeine nap outweigh solely napping, solely drinking coffee, or doing both at random intervals. You wouldn’t get the same effect if you were to drink caffeine 2 hours before you took your nap. Similarly you wouldn’t get the same degree of effect if you drank coffee several hours after your nap – the timing matters.
Restorative effect of a nap: There are numerous psychological benefits associated with napping. Taking a 20 minute power nap has the potential to improve cognitive performance and energy levels for the second half of the day. Napping may help with memory formation, information retention, and the processing of novel stimuli.
Coffee Naps Improve Driving Performance
There are several studies highlighting the benefits of coffee naps among truck drivers. Truckers tend to drive long distances and may face risk of sleep deprivation, leading to an increased number of errors on the road. Therefore they are often encouraged to take naps when needed or consume caffeine. That said, it is clear that a caffeine nap may yield the most significant benefit compared to either method as a standalone option.
Studies analyzing the effects of a “coffee nap” date back to the late 1990s. In a 1996 study, researchers compared the effects of caffeine in coffee (150 mg), a <15 minute nap, and a coffee placebo on 10 truck drivers. They analyzed these effects during 30 minute rest periods between two “1 hour” afternoon drives in a car simulator.
Results suggested that caffeine intake and napping both reduced driving impairments (e.g. errors), subjective reports of sleepiness, and EEG (brain waves) associated with drowsiness. The amount of sleep during naps was subject to individual variation, and caffeine was noted as yielding more consistent alertness effects. Taking a “break” from driving without the caffeine or the napping did NOT reduce driving impairments.
Approximately a year after (1997) the aforementioned study, researchers speculated that combining a nap <15 minutes and caffeine consumption may lead to greater synergistic benefit in reducing sleepiness and performance errors than solely napping or solely drinking coffee. In this new study, they analyzed 12 sleepy individuals with combined treatments. The treatment was administered during a 30 minute break prior to a long (2 hour) afternoon drive in a car simulator.
Comparisons for those taking “coffee naps” were 200 mg caffeine only and a placebo. The placebo group was documented as showing EEG signs of sleepiness and compromised performance. The group receiving “caffeine only” experienced significantly increased alertness and better performance by comparison. However the “coffee napping” group eliminated all signs of sleepiness and compromised performance.
Even naps considered “nonsleep” or “dozing” were found to be effective when used in conjunction with coffee. Although these studies are small, they demonstrate the ability of both caffeine and napping (especially when utilized together) to improve mental performance and reduce potential errors – both of which are extremely important for truckers.
- Source: http://www.ncbi.nlm.nih.gov/pubmed/8936399
- Source: http://www.ncbi.nlm.nih.gov/pubmed/9401427
How To Take a Coffee Nap (Instructions)
So you want to know how to take a caffeine or coffee nap for maximum overall benefit? It’s not rocket science, but it may take a bit of planning. Before you attempt the nap, you should have a cup of coffee on hand or some caffeine source.
1. Get a cup of coffee
To fit the official criteria for a coffee nap, you’ll want to have a cup of coffee on hand. You can brew the coffee yourself or purchase it from a reliable vendor. You’ll want to make sure that the coffee is derived from a clean source, without any unnecessary additives (e.g. sweeteners) or toxins. Excess sweeteners may result in a glucose surge, interfering with your ability to nap.
There are many viable substitutes for coffee in terms of caffeine content (e.g. sleeping pills). You should aim to consume somewhere around 100 mg to 200 mg of caffeine if you want to mimic the scientific studies. However, many “energy drinks” and sodas contain unhealthy additives that could interfere with your nap; this is something to consider.
2. Find a place to nap
Once you have your coffee on hand, you don’t need to drink it immediately. You should then find a comfortable place to take a nap. You’ll want to find an area that is free of loud noises and that allows you to lie down or fully extend your body.
Some workplaces have specific “napping rooms” for their employees to nap. If you don’t happen to have a designated napping area at your work, you may need to get creative. If you happen to be at home or are staying in a hotel, your bed may be the most appealing option.
3. Set alarm clock for 20 minutes
After you’ve secured a cup of coffee and located a suitable place to nap, you’ll want to set an alarm for 20 minutes. One app that works great for this is “sleep cycle” – it has a variety of comforting alarm options, and allows you to tweak the volume. You could set the alarm for less than 20 minutes if you want such as 15 minutes, but 20 minutes is considered ideal.
Anything beyond 20 minutes may result in feelings of grogginess and may interfere with the stimulatory properties of the caffeine. Perhaps 25 minutes may work for some people, but most experts recommend striving for 20 minutes.
4. Drink coffee
After you’ve set your alarm, drink your coffee. You may want to use the bathroom before you take your nap and consume your coffee. If you have a full bladder, drinking a full coffee may result in you waking from your nap to use the bathroom.
After you’re finished drinking coffee, you’ll want to start your nap. For those that used an alternative to coffee (e.g. caffeine pills), you’ll also want to start napping as soon as its down the hatch.
5. Start napping
Immediately upon consumption your coffee or caffeine source, you should start sleeping. Your alarm should already be set for 20 minutes, and you should attempt to fully sleep. Many people think that if they drink coffee and “rest” they’ll get the same effect. Merely “resting” after consumption of coffee will not produce the same effect.
You should be attempting to achieve light sleep for a 20 minute window. In other words, close your eyes, and try to fall asleep. Resting does not give you the same benefit as an actual nap, but your performance will still improve from the coffee.
6. Wake up
If you did this correctly, you should wake up after 20 minutes and start working on a cognitively-demanding task. Your brain will be primed for alertness and you should feel more energy from the “coffee nap” than you would have from coffee-only or napping-only. Based on the scientific evidence, you should feel more invigorated than usual throughout the afternoon.
How to enhance coffee naps: Bright lights and face washing
There is evidence that a coffee nap isn’t the only way to enhance alertness for the rest of the day. In fact, a 2003 publication highlighted a couple more interventions such as: bright light exposure (2000 lux) and face washing. Both the exposure to bright light and the face washing were performed for 1 minute immediately upon waking from a nap.
This study involved 10 young, healthy adults and documented the effects of: napping-only, 20 minute naps, caffeine naps (200 mg caffeine), napping + bright light exposure upon waking, napping + face washing upon waking, and no-napping. While the caffeine nap was most effective at reducing subjective sleepiness and performance compared to the other combinations, napping + bright light exposure and napping + face-washing were also beneficial.
Theoretically, you could take a caffeine nap, expose yourself to a bright light (at least 2000 lux) upon waking and wash your face for maximum benefit. It is unknown how much additional benefit could be derived from adding the bright light and face washing to enhance performance and reduce sleepiness.
- Source: http://www.ncbi.nlm.nih.gov/pubmed/14652086
Frequently Asked Questions (FAQs)
Below is a list of frequently asked questions in regards to coffee naps.
What if you’re not good at napping?
If you’re not good at napping, the goal should be to try your best. Set yourself up by getting into a comfortable environment without noisy distractions. Then close your eyes and relax as you drift off to sleep. Even if you aren’t able to fall fully asleep, there’s evidence that half-sleep or “nonsleep dozing” may provide you with similar results. While it is optimal to get light sleep, even if you’re “dozing” it’s better than merely resting.
Won’t the caffeine prevent me from napping?
If you ingest too much caffeine and/or are pounding coffee all morning prior to your nap, it may impair your ability to get sleep. Too much coffee, especially if combined with another stimulatory substance (e.g. nicotine) may severely hamper your ability to engage in a coffee nap. However, if you have one cup of coffee when you first wake up, and abstain from drinking until your afternoon coffee nap, it shouldn’t inhibit your ability to nap.
If you find yourself unable to even “doze” for 20 minutes, try to reduce the amount of coffee you consume in the morning or strive to lower your stress level. If you have high levels of adrenaline or are on a pharmaceutical drugs (e.g. ADHD medications) that alter neurotransmitter levels, your ability to successfully nap may be compromised.
What is the best time of day for a coffee nap?
The optimal time of day for a coffee nap is between 10 AM and 2 PM. Obviously there may be significant individual variation in terms of what time fits with a person’s lifestyle or work schedule, as well as what time fits best with a person’s circadian rhythm. If you engage in a caffeine nap after 2 PM, it may interfere with your nighttime sleep schedule, serving as a cause of insomnia.
Those that find themselves unable to sleep at night after a coffee nap between 12 PM and 2 PM may need to take a coffee nap at an earlier time slot. Although a coffee nap may be appealing, it is important to avoid compromising your nighttime sleep onset as a result of ingesting caffeine too late in the day. So whenever considering a coffee nap, a good rule of thumb is that earlier is better.
How much caffeine is required for a coffee nap?
Most studies highlighting the benefits of “coffee naps” use doses of 200 mg of caffeine per cup of coffee. Some people are sensitive to small amounts of caffeine, while others may tolerate even more than 200 mg. It is important to consider the fact that higher doses may result in symptoms of insomnia.
To preserve your circadian rhythm and nightly sleep schedule, you should avoid high amounts of caffeine in the afternoon. The combination of the nap along with standard amounts of caffeine should elicit beneficial effects.
Can you replace coffee with another source of caffeine?
If you don’t like coffee, there are plenty of other sources of caffeine for you to choose from. You may decide to take a “tea nap” or even a “caffeine pill” nap. Keep in mind that certain beverages (e.g. sodas) may not contain enough caffeine for you to achieve the same effect.
From a health-conscious perspective, sodas and energy drinks contain significant amounts of sugars and artificial additives, all of which may interfere with your ability to successfully nap. Therefore you should be highly picky about your caffeine source, making sure that it’s as clean as possible with minimal toxins and additives.
Have you ever taken a coffee nap?
If you have taken a caffeine or coffee nap, feel free to report your subjective experience. Did you feel increases in energy that you wouldn’t have been able to attain from a standalone nap or cup of coffee? You may also want to discuss whether you frequently take coffee naps, how much caffeine you typically ingest, as well as the average duration of your naps.