To Nap or Not to Nap: Is That the Question?

By Kerrin Leon White - September 29, 2000

"If you didn't sleep so much, you wouldn't be so sleepy!"

Did you ever hear such advice from well-meaning friends or relatives?

In the parlance of social medicine, this kind of penetrating diagnostic formulation falls under the heading: "Blaming the Victim."

Its numerous derivatives serve many useful purposes. Just one of these is to dismiss a person's problem by alleging that the sufferer could solve it easily by a simple act of will power.

Consider a rebuttal: "If you didn't eat so much, you wouldn't be so hungry!"

Nonsense, right? But even on this reductio ad absurdum, not everyone would disagree!

So, what about naps? Are they mostly a symptom of laziness? Or are they a good idea, as people in "siesta" countries seem to believe?

The truth may lie in different answers, depending on the situation and the type of nap.

The latest issue of Sleep, a medical journal specializing in research on sleep and its disorders, brought this to mind. One article should interest even people without disorders of excessive sleepiness. It dealt with the effectiveness of naps in overcoming the effects of sleep loss.

[Note: To be exact, the lengthier actual title is "Maintenance of Alertness and Performance by a Brief Nap After Lunch Under Prior Sleep Deficit," authored by Masaya Takahashi DMSc and Heihachiro Arito DMSc, of the National Institute of Industrial Health in Kawasaki, Japan. The article can be found in Volume 23, Number 6, pages 813-819, in an issue dated September 15, 2000.]

In essence, the researchers had 12 young, healthy students limit their sleep to only 4 hours for one night, on two occasions. The following day, each subject had either no opportunity to nap, or 15 minutes in bed available to nap right after lunch (from 12:30 to 12:45 p.m.).

Both before and after lunch, at intervals of about 1.5 hour, subjects completed tests of memory and logical reasoning, and rated their own subjective sleepiness. After a nap averaging 10 minutes in duration (measured by sleep polysomnography), they felt less sleepy, and performed better on logical reasoning, than without a nap.

Like a lot of clinical research, this study serves to confirm what some might consider obvious, but it surprised me to learn that even a nap as short as 10 minutes could reverse the adverse effects of losing half a night's sleep.

On the other hand, haven't the virtues of a brief nap been proclaimed by the personal experience of at least one President?

Excessive sleepiness during the day most often results from people just not allowing themselves enough time in bed to get the normal 8 hours of sleep. In this commonplace situation, short naps seem to serve a useful purpose.

If I were an employer trying to get the most accurate and productive work out of my employees, I might even consider allowing them an extra 15-30 minutes off after lunch-provided they spent that time in a specially designed "nap room," conducive to sleep and not to running errands, making phone calls, reading the newspaper, etc.

Of course, long naps (an hour or more), and naps taken late in the day, run counter to the rules of good sleep hygiene. They may make it more difficult to sleep at night; this may be important for people who suffer from nighttime insomnia.

Moreover, long naps may help perpetuate the frequent and fruitless practice of trying to squeeze more awake time out of a day than the body really allows. This harmful habit reflects more concern over how much one does than how well one does it.

That is a losing proposition, unless you count only the extra "pennies" that a poorly functioning person adds to income by working longer hours, in all likelihood accomplishing less would be possible in a shorter time at optimal levels of functioning.

Incidentally, these results may also apply to sleepy drivers, a menace of increasing concern, making it well worthwhile for not only long-haul truck drivers and vacationers, but even for ordinary commuters, to have available frequent rest stops designed to make brief naps more practicable. Of course, it would cost public money, but how much cost results from the half of all accidents thought to result from sleepy drivers?

Setting aside the issue of napping among "normal" people, what about people with disorders of sleep that result in excessive daytime sleepiness? For them, is there really a choice of "to nap or not to nap?"

The most common disease causing excessive daytime sleepiness is obstructive sleep apnea. This results in any and all sleep a person gets--at night or in daytime naps of any length--being disrupted by respiratory events that cause "arousals" (not the same as awakenings), a disruption which prevents the continuous sleep necessary to feel refreshed.

Such people awaken in the morning, even after more than eight hours of sleep, feeling tired, and likewise awaken tired from even the longest nap.

The association of this kind of oversleeping with constant daytime sleepiness may have fostered the popular superstition that "sleep causes sleepiness."

For these people--who often take very long naps--no amount of napping provides relief from sleepiness.

So, you might argue, they should stop napping. But can they?

Sleepiness, like hunger and thirst, has a way of compelling compliance to its demands, however unsatisfying that subjugation may prove. Thus, people dying of thirst may drink salt water or urine, and those starving to death may eat grass or wood.

Under duress of physical need, few have the iron will to resist just the illusion of relief. Consider how difficult it is to resist even a biological drive without fatal consequences if unsatisfied--sex!

Some people with excessive daytime sleepiness resulting from sleep apnea can succeed in delaying sleep in situations that would make it grossly inappropriate--as at a staff meeting or while driving. Some can't, however high a price they may pay for giving way to sleepiness. Don't you hear them snoring at important conferences? Do you think they bother to attend, then don't bother to pay attention, because they're slothful, or bored?

Those who do stay awake may still pay the price of slow and inaccurate thought processes, which might have made it better for them to have stayed in bed!

Note that the role of naps may differ greatly, depending on the disease that underlies excessive daytime sleepiness.

The person with narcolepsy often naps only briefly, and afterwards awakens more alert, though maybe soon in need of another short nap. Therefore, allowance of opportunities for brief naps throughout the day may improve functioning enough to make the difference between disability and employability in these people.

So, let's go back to the question in the title--"To Nap or Not to Nap?"

The answer depends on at least two distinct and crucial questions: for people with normal nighttime sleep habits, how long a nap? And, for those with excessive daytime sleepiness, is this due to self-imposed sleep deprivation, narcolepsy, or sleep apnea, or something else?

As an amusing sidelight to my borrowing and bastardizing the famous quote from Shakespeare's Hamlet (III:1:65), let me offer a tidbit for thought on Hamlet's real words: "To sleep: perchance to dream: ay, there's the rub. . ."

Hamlet referred to the sleep of death, but no doubt had in mind the dreams of nightmare, probably one source for the earliest human visions of hell.

Most short nappers, with the noteworthy exception of those with narcolepsy, need not fear bad dreams. The first cycle of Rapid Eye Movement (REM, or dreaming) sleep takes about 90 minutes of sleep time to begin!
For more information on Sleep Apnea, please see our Sleep Apnea Section.