A nap can make you smarter, faster, and safer than you would be without it, and napping should be widely recognized as a powerful tool in battling fatigue. While the short-term effects of napping on attention, concentration, and reaction time may take effect even after a single nap, the mid- and long-term benefits of napping may only be considered in those who do so regularly. There are different types of naps to be sure, that depend upon its length, the circadian position, and one’s own sleep architecture. Napping habits can change within an individual's lifespan, from the progressive decrease in nap length and nap episodes of early childhood to the midday naps of adulthood. They can be culturally driven such as in afternoon or midday sleep or a siesta of the Mediterranean culture, which delves to counteract excessive work hours. In China, the right to nap at work was written into the constitution of 1948 to ensure better working conditions and productivity. So defined, it is a voluntary episode of sleep ranging from several minutes to nearly 90 min of sleep.
Physiological, cognitive, and public health prophylactic effects of napping is best understood by health care providers in the context of a countermeasure for sleep debt. Napping in that context can lead to physiological benefits associated with its stress-release effects, blunting cortisol and noradrenaline responses, reducing high blood pressure, and normalizing immune components such as circulating cytokines, and even reducing pain sensitivity associated with sleep deprivation and systemic illness. Napping facilitates the recovery of alertness reduced by sleep loss and can improve memory consolidation. The value of a prophylactic nap has been used medically to decrease cardiovascular risk factors in middle-aged adults, and conversely in elderly persons who take long (>60 min) and regular naps. In short, napping can also be associated with improved working performance and in reducing accidental injuries especially among persons sleep-deprived.
With the growing number of people chronically sleep restricted because of study and work schedules, commuting times, and subjected to increased access to connected media, napping may be the antidote to sleep debt especially when sleep-like activity intrudes the awake brain, leading to cognitive deficits. The role of napping and its timing on memory performance is less well studied, but current advocates of a nap suggest it should be integrated into children’s educational program as a useful pedagogic tool especially when they report mental or physical fatigue.