Can power naps help you stay alert and more productive?

In his 2017 book Why We Sleep, neuroscientist and sleep researcher Matthew Walker recalls how the term “power nap" was coined. In the 1980-90s, renowned sleep researcher David F. Dinges and Mark Rosekind, then administrator of the National Highway Traffic Safety Administration in the US, conducted a series of studies on the pros and cons of power napping in “the face of unavoidable sleep deprivation". Their work focused on the aviation sector, especially pilots.

Dinges and Rosekind figured that “inserting a nap" at the beginning of an “incoming bout of sleep deprivation" would provide a buffer and protect the brain from major lapses in concentration. This was key for pilots who have to stay alert over long distances. “They had discovered the sleep equivalent of the medical paradigm of prevention versus treatment," Walker says in his book. “These short sleep bouts, taken early, also reduced the number of times the pilots drifted into light sleep during the critical, final ninety minutes of flight." Dinges and Rosekind initially suggested the terms “prophylactic naps" or “planned naps" to the US Federal Aviation Administration. The FAA instead suggested “power napping", as it was more “fitting with leadership- or dominance-based job positions".

With a large number of people working from home these past few weeks, their screen time has increased exponentially while breaks—common at workplaces—are virtually non-existent. The ensuing physical and mental fatigue means people have taken to shorter naps during the day to recharge their batteries. “It has been seen that these naps do help in making you more alert, attentive and consolidating your memory. It also improves your mood and performance. These are some of the advantages of a power nap," says Vivek Nangia, director and head, pulmonology, medical critical care and sleep disorders, Fortis Hospital, Vasant Kunj, Delhi.

A 2017 paper, Exploring The Nap Paradox: Are Mid-day Sleep Bouts A Friend Or Foe?, by University of Massachusetts researchers explains the cognitive benefits of midday naps: “Following sleep deprivation, sleep restriction, or even a normal night of sleep, sleepiness increases with time spent awake, while cognitive abilities, such as working memory, decrease. However, a mid-day nap has been shown to effectively assist with ‘recovery’ of these faculties." The researchers say that in addition to “minimizing sleepiness", naps also promote some essential functions of the human brain, like “emotion processing" and subsequent learning.

Dr Nangia says there are, however, certain rules for a good power nap. “The duration of these naps should not be more than 20-30 minutes," he says. This is to avoid sleep inertia where, despite taking a nap, you wake up feeling dull and groggy. Longer, irregular power naps often lead to this situation. “The environment around you should be neat, clean and calm.... If you are sleeping and still not waking up fresh, then it won’t serve the purpose," adds Dr Nangia.

Another key factor in how power naps could affect your energy and productivity levels is the overall quality of your night-time sleep. “If you see, 85% of the mammals on Earth have a dual-phase sleep response: They sleep, wake up, sleep again and wake up again. Humans are among those few species who sleep only once and at a stretch at night," explains Dr Nangia.

A February 2009 article on insomnia in Harvard Men’s Health Watch explains how studies in shift workers and airline crews show that power naps as short as 20 minutes can improve alertness, psychomotor performance and mood. But it warns that if your “nap is too long you may find yourself awake in bed at night".

Dr Nangia says it is essential, therefore, to keep your regular sleep cycle on track so you don’t need power naps. “You need to regularize your sleep cycle. If you are sleeping well at night, you should ideally not require power naps," he says.