As humans, we share specific characteristics with other mammals (e.g. hair or fur growing from the skin, bones in the middle ear and in the lower jaw, and milk production in females). Additionally, more than 85 percent of mammals nap. These mammals are considered poly-phasic sleepers, which translates into sleeping in several blocks of time throughout the course of a day. Currently, many humans are mono-phasic sleepers where they sleep in one block of time during the night.
Evidence suggests humans were historically bi-phasic sleepers, whereby they slept in two blocks of time. Drawn from diaries, court records, and medical texts, a first and second sleep is often referenced. A historian, A. Roger Ekirch notes in his book, At Days Close: Night in Times Past, humans went to bed approximately two hours after dusk and slept a few hours, awoke for one to two hours, and then went back to sleep until the break of dawn. This leaves to question, is it really a sleep issue for those who awake in the middle of the night? Might it be a more natural rhythm for their body?
Modern Society and Sleep
Ekirch notes when modern society began emerging, bi-phasic sleeping started decreasing in its prevalence. What followed around the late 19th century was insomnia issues surfacing with corresponding literature discussing the phenomenon. In the 1990s, a psychiatrist and researcher, Thomas Wehr became aware of bi-phasic sleeping patterns. Curious, he performed a sleep experiment to determine if it was a natural, human inclination. The results suggested that bi-phasic sleeping was biologically based and a natural tendency for humans. With this, the afternoon nap could be considered an attempt to reclaim to a lesser degree, bi-phasic sleeping.
In some cultures, napping is integrated into the cycle of the day, usually following lunch. Businesses close down for two hours to accommodate the meal and napping tradition. However, the National Sleep Foundation (NSF) notes the United States appears to be increasingly sleep deprived. Since it does not look like our culture will be accommodating nap time anytime soon, there is nothing to say you cannot create your own napping tradition. The NSF does indicate a 20-30 minute nap earlier in the afternoon can increase short-term alertness. However, taking a nap later in the day can interfere with your evening sleep.
Creating Nap Time
How can you find nap time if you need it? Consider napping in your car after eating lunch during moderate weather, close an office door, or find a quiet space where you will not be disturbed, or if you live close by, flex your schedule where you can go home to eat and nap. The NSF reports three U.S. presidents, John F. Kennedy, Ronald Reagan, and George W. Bush were nappers, as well as Albert Einstein and Thomas Edison. If they recognized the benefits of napping for themselves, perhaps the American culture will begin to wake up to napping.
Napping can provide a host of benefits worthy of pursuing, but it can also have unpleasant effects.
Benefits of Napping
The benefits of napping are numerous, including
- Restores alertness
- Boosts mood
- Increases performance
- Decreases mistakes
- Decreases accidents
- Provides relaxation
- Reduces stress
- Supports rejuvenation
Woes of Napping
- Sleeping beyond 30 minutes can create disorientation and grogginess, called sleep inertia.
- Sleep inertia can be more challenging for those who are already sleep deprived.
- Napping too long or too late in the day can negatively impact the quality of night sleep.
Overall, the NSF suggests napping within a 10-30 minute time frame appears to do the body good. Keep in mind, everyone is different. Listen to your body. Is it calling out for a nap on a consistent basis? Do you find yourself waking in the middle of the night? If so, try adjusting your schedule and be your own experiment. Perhaps the results will yield some interesting findings.