Siesta



A siesta (, original Spanish pronunciation ) is a short nap taken in the early afternoon, often after the midday meal. Such a period of sleep is a common tradition in some countries, particularly those where the weather is warm. The word siesta is Spanish, from the Latin hora sexta - "the sixth hour" (counting from dawn, therefore noon, hence "midday rest").

Origins of the Iberian siesta
The siesta is the traditional daily sleep of the Iberian peninsula and, through Spanish influence, of Latin American countries. Afternoon sleep is also a common habit in the Philippines, China, India, Italy, Greece, Croatia, Malta, the Middle East and North Africa. In these countries, the heat can be unbearable in the early afternoon, making a midday break in the comfort of one's home ideal. However, in some countries where naps are taken, such as Northern Spain, Southern Argentina, and Chile, the climate is similar to that of Canada and Northern Europe. Besides the climate, in many countries with this habit it is common to have the largest meal of the day in the afternoon, in contrast with other countries where only a lighter lunch is taken.

The original concept of a siesta was merely that of a midday break. This break was intended to allow people time to be spent with their friends and family.

Others suggest that the long length of the modern siesta dates back to the Spanish Civil War, when poverty resulted in many Spaniards working multiple jobs at irregular hours, pushing back meals to later in the afternoon and evening.1 However, this hypothesis sounds unlikely, considering that the siesta tradition is very common in Latin America and other countries with Hispanic influence, much before the Spanish Civil War.

Although colonized by Portugal, being part of South America, and clearly dominated by equatorial to tropical climate, Brazil stands in glaring cultural contrast in regard to the adoption of an afternoon nap.

The afternoon nap
Today, the term "siesta" refers to a short nap (15 to 30 minutes) taken after the midday meal. Siestas are traditionally no longer than 30 minutes and are more of a light rest than any kind of serious sleep. Other names for a siesta may include: cat nap, snooze, doze, kip, winks, power nap, or simply, afternoon nap.

In Argentina, the siesta is supposed to be between 13:00 and 16:00, and in some regions, such as Santiago del Estero, it is called "sacred" because people do not want to be disturbed. Business hours in these regions are usually 8:00 to 12:00 and 16:00 to 20:00. Other business hours (extended) vary between 6:00 to 13:00 and from 15:00 to 21:00, but most either add or shift 30 minutes to the regular 8-12/16-20 times. In bigger cities such as Buenos Aires, and with the time and money it takes to commute, businesses just use 9-to-6 time.

In Malta, business hours are usually between 9:00 and 12:30 and from 16:00 to 19:00 to enable workmen to return home during the break, have lunch and possibly take a siesta. Due to the shortness of distance between the place of business and their residence, this practice is not uncommon.

In Iran, business hours are around 6am to midday, then workers relax with long lunches usually eaten outside of the place of employment, then the nap occurs after lunch when workers go home, and return to work around 15:30 to work until around 20:30. It is typical to see during the midday to 14:30 whole business centers including the Tehran Bazaar and other places of business virtually shut down in the major cities during the siesta.

Older, pre-teenage children are usually incapable of napping, but acquire the ability to nap as teenagers. Some people sleep the whole time (up to two hours), but most people watch television or take a short 15 to 30 minute nap. In any case, the streets are deserted at the siesta time in siesta-practicing cities.

Biological need for naps
The timing of sleep in humans depends upon a balance between homeostatic sleep propensity, the need for sleep as a function of the amount of time elapsed since the last adequate sleep episode, and circadian rhythms which determine the ideal timing of a correctly structured and restorative sleep episode. The homeostatic pressure to sleep starts growing upon awakening. The circadian signal for wakefulness starts building in the (late) afternoon. As Harvard professor of sleep medicine Charles A. Czeisler puts it:
 * "The circadian system is set up in a beautiful way to override the homeostatic drive for sleep."

Thus, in many people, there is a dip when the drive for sleep has been building for hours and the drive for wakefulness hasn't started yet. This is, again quoting Czeisler, "a great time for a nap." The drive for wakefulness intensifies through the evening, making it difficult to get to sleep 2-3 hours before one's usual bedtime when the wake maintenance zone ends.

In some individuals, postprandial dip, a brief drop in blood glucose levels caused by the body's normal insulin response to a heavy meal, may produce drowsiness after the meal that can encourage a nap. However, the appearance of the dip is primarily circadian as it occurs also in the absence of the meal.

Siesta in other cultures
The concept of a midday nap is also prominent in other tropical or subtropical countries, where the afternoon heat dramatically reduces work productivity. The Washington Post of February 13, 2007 reports at length on studies in Greece that indicate that those who nap have less risk of heart attack. 

In South Asia, the idea of a post-lunch nap is common, and the idea of going to sleep after a light massage with mustard oil to induce drowsiness was very popular before industrialization. It was also very popular to consume a light snack during this ritual; it was thought that this practice would make one a better person. In Bangladesh and Indian Bengal, the word which describes the concept is bhat-ghum, literally meaning "rice-sleep" (nap after consuming rice).

Afternoon sleep is also a common habit in China and Taiwan. This is called xiuxi or wushui in Chinese. Its main difference from the siesta is that it lasts between two and three hours. It occurs after the midday meal and is even a constitutional right (article 43, Right to rest). Almost all schools in Mainland China and Taiwan have a half-hour '"nap period'" right after lunch. This is a time when all lights are out and one is not allowed to do anything else than sleep.

Some Japanese offices have special rooms known as napping rooms for their workers to take a nap during lunch break or after overtime work.

In Islam, it is encouraged to take a short nap around 15-30 minutes before the time for Dhuhr prayers, with the intention of doing tahajjud later in the night.