Written by Lucy Haura
Edited by Renee Lee
If you are unlucky—or depending on how you view it, lucky—you might’ve come across the term “caffeine nap” in your time as a student. The term, defined as the act of consuming coffee or caffeine immediately prior to a nap, has been shown to improve alertness during the day. But is this strategy really an effective way of working through that to-do list, or is it a fatigued person’s attempt at encouraging themselves to continue?
Photos by Julia Leavitt jal569@cornell.edu
Understanding how a caffeine nap might extend mental performance first requires an understanding of how caffeine works in the brain. Caffeine stimulates the central nervous system by blocking adenosine receptors, in which adenosine is a byproduct of neural energy use that builds up the longer you’re awake. The activation of the receptors dials down the release of excitatory signals, essentially reducing activity of wake-promoting areas and encouraging sleep. Caffeine then acts as an antagonist by binding to the receptors without activating them, preventing adenosine from delivering its signal and promoting feelings of drowsiness.
Before diving into ways to wire getting more wired, it's also important to note the safety concerns regarding caffeine consumption. Caffeine is generally regarded as safe, for daily intakes up to 400 mg. However, high amounts can lead to nausea, jitteriness, and nervousness, and high daily intake can cause withdrawal symptoms like headaches and muscle tremors. This tolerance can be explained by requiring more caffeine to attain the same stimulation as before, due to upregulation of adenosine receptors in the brain, and as increased clearance rate of the stimulant, shortening the effect.
Some studies have examined the effects of caffeine administration on performance over periods of extended wakefulness. These periods, especially common within military, emergency and healthcare practices, and, occasionally, students, are spans of time where hours of work extend past 24 hours. These extended periods of being awake not only contribute to sleep deprivation and decreased vigilance, but can increase risks of workplace incidents and accidents. Studies showed that caffeine reduced performance impairment compared to a placebo, but not self-reported fatigue. Those who use caffeine to stay awake for a long time might feel like caffeine isn't effective even while their impairments in performance might be reduced.
Photos by Julia Leavitt jal569@cornell.edu
A caffeine nap, in this instance, may help by providing a brief bit of respite and recharge, while allowing for the effects of the caffeine to kick in. One pilot study had participants consume 200 mg of either caffeine or decaffeinated coffee, as a placebo, prior to a 30 minute nap. In the 45 minutes after the nap, subjects showed improved attention and subjective fatigue. Another studycomparing a combined caffeine-nap treatment with a placebo-nap treatment and their effects on driving incidents showed similar findings. Both the placebo and the nap treatment resulted in temporary decrease in driving mistakes, likely due to the sleep itself, but the placebo participants experienced an increase in fatigue about 90-120 minutes after the nap, which is typical of the mid-afternoon circadian surge, or slump in wakefulness. This surge was eliminated with the caffeine-nap.
But how can this possibly translate to an engineer fretting over circuits at 2 AM or a fashion student pulling an all-nighter for their final piece in their portfolio? A “caffeine nap” might help reduce feelings of sleepiness while extending performance and vigilance. By reducing the feeling of fatigue with a short nap, the stimulatory effects of caffeine can be used to their fullest extent, allowing one to finish grinding out their case study or put the final touches on their architecture model. It is worth noting that caffeine late at night can disrupt the sleep you do get afterward, since its half-life is several hours. While caffeine acts on the receptors without activating them, adenosine continues to accumulate, causing the crash when caffeine wears off. So caffeine naps, a drowsy delusion, it may not be, but a dream or nightmare strategy? That is up for you, and continued research, to decide.
Note: This article does not encourage excess consumption of caffeine. These potential strategies are not equivalent to adequate sleep, which is essential for both short term functioning and long term health.
(Lucy Haura ‘28 is in the College of Human Ecology. She can be reached at lah333@cornell.edu )
