Napping Twice Daily: A Guide To Sleeping Twice A Day

Sleep is an essential part of our lives, but is sleeping once a day the best way to do it? Some people think not. In fact, there is a growing movement of people who are embracing biphasic sleep, which involves two sleeps in a 24-hour period. This isn't a new idea, it's actually in our history. So-called bimodal sleeping was the favoured method before the industrial revolution. But is it a good idea?

The history of biphasic sleep

The ancient Egyptians are often credited with being the first civilization to adopt a biphasic sleep pattern, with evidence dating back to at least 2000 BCE. The Egyptians would sleep for four to six hours at night, then wake up for a period of rest or leisure activities before returning to sleep for another four to six hours. This pattern was described by the Roman historian Plutarch, who wrote that the Egyptians "interpose a set of leisure hours between the two periods of sleep."

Biphasic sleep was also common in ancient Greece, where it was known as "first sleep" and "second sleep." The Greek philosopher Aristotle wrote about biphasic sleep in his work "History of Animals," stating that it was a natural and healthy way to sleep. The Greeks would typically sleep for three to four hours, then wake up for a period of time before returning to sleep for another three to four hours.

During the Middle Ages, biphasic sleep became less common in Europe as the monastic practice of rising early for morning prayers became more widespread. However, it was still practiced by the general population in rural areas and among the working class. The word "siesta," which refers to a midday nap, comes from the Latin "hora sexta," or "sixth hour," as it was traditionally taken around noon, six hours after waking.

In the early modern period, biphasic sleep began to fall out of favor as the Industrial Revolution led to a shift towards a more standardized sleep schedule. The rise of factories and the need for a consistent workforce led to the adoption of a monophasic sleep pattern. This shift was also influenced by the growing belief that biphasic sleep was a sign of laziness and a lack of discipline.

Historian A. Roger Ekirch has argued that before the Industrial Revolution, interrupted sleep was dominant in Western civilization. He found more than 500 references to a segmented sleeping pattern in documents from the ancient, medieval, and modern world, including in works of literature such as Geoffrey Chaucer's "The Canterbury Tales" and William Baldwin's "Beware the Cat."

Ekirch's research suggests that the first sleep and second sleep were common in medieval England, and he found references to these terms in other Romance languages as well as in the language of the Tiv of Nigeria. The period of wakefulness between the two sleeps was known as "the watch," a time often used for prayer, reflection, and interpreting dreams, which were more vivid at that hour.

Despite the widespread adoption of monophasic sleep, biphasic sleep has experienced a resurgence in recent years as research has shown that it can have numerous health benefits, including improved mood, increased productivity, and reduced risk of certain health conditions.

The benefits of biphasic sleep

Biphasic sleep, also known as bimodal, diphasic, segmented, or divided sleep, is a sleep pattern where a person sleeps in two segments per day. This can mean a longer nighttime sleep and a shorter daytime nap, or two nighttime sleep segments with a waking period in between.

A More Natural Sleep Pattern

Some researchers argue that biphasic sleep is a more natural sleep pattern for humans. Before the industrial era, many people across different continents and cultures followed a biphasic sleep schedule. The advent of electricity and the modern industrial workday are thought to have contributed to the shift towards monophasic sleep patterns.

Health Benefits

Midday napping has been linked to improved cognitive performance, with shorter naps reducing sleepiness and improving alertness and cognitive function. Longer naps of over 30 minutes can also produce longer-lasting cognitive benefits, although the napper may experience a period of grogginess upon waking.

Productivity

Some people adopt a biphasic sleep schedule to maximise their productivity, creating more time for tasks and activities during the day.

Historical Evidence

There is historical evidence that humans used to naturally follow a biphasic sleep schedule. In pre-industrial societies, people would often go to bed a couple of hours after dark, wake up a few hours later, and then fall back asleep for their second sleep phase.

Cultural Norms

Biphasic sleep is still practised in various parts of the world, such as Spain, Italy, and Greece, where residents take a 60- to 90-minute siesta during the day and then sleep for five to six hours per night.

Individual Variation

Ultimately, the best sleep pattern for an individual may vary. While some people find that biphasic sleep feels natural, others feel better on a monophasic sleep schedule. Consulting a doctor or sleep expert is recommended before making any radical changes to your sleep schedule.

The drawbacks of biphasic sleep

While biphasic sleep may have its benefits, there are some potential downsides to this sleep pattern.

Firstly, transitioning to biphasic sleep can be challenging and may involve an adjustment period. During this time, individuals may experience increased tiredness, grogginess, and irritability.

Secondly, maintaining a biphasic sleep schedule can be difficult for those with strict work or family commitments. It may also disrupt social routines, requiring earlier bedtimes or napping during work hours, which can be challenging to fit into a modern lifestyle.

One of the main concerns with biphasic sleep is the risk of sleep deprivation. Insufficient sleep can lead to poor sleep quality and increase the likelihood of serious health issues such as heart disease, kidney disease, diabetes, stroke, high blood pressure, obesity, and depression. Sleep deprivation can also impair cognitive performance, with studies showing that daytime napping in children reduces attention span and vocabulary, and correlates with poor sleep quality.

Additionally, there is a lack of extensive research on the long-term effects of biphasic sleep. While it may offer benefits in terms of energy levels, alertness, and cognitive function, the potential drawbacks include negative physical and mental health outcomes, as well as adverse consequences for daytime performance.

Finally, while biphasic sleep may be a natural pattern for some, it is not feasible for everyone. It is important to consult a physician before making significant changes to your sleep cycle, especially if you have any chronic health conditions, as altering sleep patterns can have potential health risks.

How to fit biphasic sleep into a modern lifestyle

Biphasic sleep, or sleeping twice a day, is not a new phenomenon. In fact, it was the favoured method of sleeping in pre-industrial times, before the advent of electricity. During this time, people would sleep for a few hours after dusk, wake up for a couple of hours, and then sleep again until dawn. This type of sleep pattern is still common in some cultures today, such as in Spain, where people take an afternoon siesta and then have dinner at a later time.

If you're considering adopting a biphasic sleep pattern, there are a few things to keep in mind. Firstly, it's important to have a strict schedule with the same bedtimes and wake-up times every day and every week. Try to align your sleep schedule with the time of sunrise, and use bright light to assist your waking if you have to wake up during the night.

The amount of time you sleep during each period should be a multiple of your REM sleep interval, which is typically about 90 minutes for the first interval, 85 for the second, and so on. The two sleep periods should also be proportional to the length of the preceding wake period.

Another thing to consider is whether biphasic sleep will fit with your work schedule and lifestyle. While it can provide increased alertness and flexibility, it may not be possible to take long naps during the day if you have a busy schedule or work a traditional 9-5 job. However, you could explore the option of nighttime biphasic sleeping, where both sleep sessions occur at night.

Finally, keep in mind that there hasn't been extensive research on the effects of biphasic sleep, so it's important to pay attention to how your body responds to this new sleep pattern. Watch out for signs that it's not working for you, such as increased irritability or difficulty focusing.

Sample Biphasic Sleep Schedules

• Two naps at night: Go to bed in the evening, wake up for a couple of hours in the middle of the night, and then return to bed for a second sleep. For example, sleep from 10 PM to 3:30 AM, wake up until 6 AM, and then sleep again until 9 AM.
• One nap at night, one nap during the day: Sleep at night (typically after midnight) and pair this with a long afternoon nap. For example, sleep from 11 PM to 6 AM, and then take a nap from 1 PM to 5 PM.
• Two daytime naps: This option is best for those who work night shifts. Go to bed around dawn, wake up for a couple of hours, and then take another long nap before your workday begins. For example, sleep from 6 AM to 10 AM, wake up until 1 PM, and then sleep again from 3 PM to 7 PM.

How biphasic sleep differs from polyphasic sleep

Biphasic sleep involves sleeping twice per day, sometimes referred to as a siesta sleeping pattern. Typically, this involves a long duration of sleep at night (5-7 hours) followed by a shorter period of sleep during the day (up to 90 minutes).

Polyphasic sleep, on the other hand, involves sleeping multiple times throughout a day, with more than two sleeping periods. Polyphasic sleepers may rest 4-6 times a day, with each sleep period lasting anywhere from 20 minutes to 3 hours.

The main difference between biphasic and polyphasic sleep is the number of sleep periods. Biphasic sleep is limited to two sleep periods, while polyphasic sleep can include various combinations of longer and shorter sleep periods throughout the day.

Some people may choose to adopt a biphasic or polyphasic sleep pattern in the belief that it will increase their productivity and provide more time for tasks and activities. However, it is important to note that changing sleep patterns can have negative effects on the body and disrupt the natural circadian rhythm.

While some people may naturally follow biphasic or polyphasic sleep schedules, polyphasic sleep can also be the result of a sleep disorder or disability, such as irregular sleep-wake syndrome.

It is always recommended to consult a doctor or sleep expert to determine the best sleep pattern for your individual needs.

Frequently asked questions