Verified by 
Key points
- Some experts recommend "segmented sleep," or dividing total sleep time into two or more blocks.
- Recent research found no evidence supporting benefits from following this kind of segmented sleep schedule.
- For some people, segmented sleeping patterns may indicate the presence of an underlying mental health disorder.
- However, sleep patterns may not be as crucial as sleep hours, making it important to prioritize getting enough sleep.
Can knowledge of how our ancestors slept truly lead us to a life of more natural—and healthy —sleeping patterns?
Authors on the Internet have been exploring that possibility, writing a spate of recent articles indicating how the ancients, as far back as early Greece, slept in segmented or “divided” phases, which were seemingly in line with human circadian rhythm. Indeed, one online article references the Odyssey, written in the 8th or 7th century BC, in which Homer reportedly mentions the “first sleep.”
In a 2015 interview, historian Roger Ekirch, a leading researcher on segmented sleep, indicates that middle-of-the-night wakefulness, often branded as a form of insomnia today, was considered “normal” before the late 19th century. It was simply a period of time that separated two sleep phases and provided an opportunity to use the toilet, take medicine, converse socially with one’s spouse or friend, put more wood on the fire, and even engage in sexual relations before returning to sleep. “Awakening shortly before midnight or at a later hour was thought completely natural,” Ekirch writes in a 2016 issue of the journal Sleep.
Prior to the lightbulb and indoor heating, nights, especially winter nights, were long and chilly, with darkness being of 12-hour duration or longer. People did not need 12 hours of sleep then nor do they need it now. So, waking in the middle of the night and finding something to do before the next phase of sleep overcame one’s eyes was not unusual.
Of course, that still leaves us with a question: Is biphasic or polyphasic sleep (segmented sleep) truly healthier and more natural than a consolidated (monophasic) seven, eight, or even nine hours of sleep?
To Sleep or Not to Sleep (in Segments)?
A segmented sleep or biphasic sleeping pattern involves sleeping in two separate segments. The term “polyphasic” applies to multiple segments, much like the sleeping patterns of infants.
Monophasic (consolidated) sleep is more the norm in today’s society. It became standard practice with the advent of the Industrial Revolution, requiring people to wake at a designated time, spend most of the daylight hours working, and then return to bed within a specific timeframe to ensure sufficient rest before repeating the entire process all over again on the following day.
Some experts tout the “benefits” of returning to a segmented sleep approach. For example, they say the mid-afternoon sluggishness that sometimes can slow us down may simply be a holdover from the segmented sleeping patterns of the ancients. But other scientists are more cautious, indicating that biphasic or polyphasic sleep patterns can lead to inadequate amounts of sleep. Indeed, the evidence suggests that many adults who voluntarily adopt a segmented-sleep lifestyle do so to increase their hours of productivity, while restricting their overall sleep time below recommended minimum hours. The risk, of course, is sleep deprivation and the health consequences associated with it.
Sleep deprivation is considered an underlying cause for certain impairments in brain function and hormone production, reduced immunity protection from disease, overstimulated appetite and weight gain, higher risk for diabetes, an overactive nervous system, chronic fatigue, even earlier death—as well as a range of psychiatric disorders, including elevated anxiety, depression, and obsessive-compulsiveness.
The Uberman Way
Reports came out 20 years ago about polyphasic sleeping based on what was called the Uberman Sleep Schedule. The program called for taking a series of 20-minute naps spread out equally throughout the day. The intent was to “compress physiologically less important stages of sleep and homeostatically upregulate stages vital for mental health,” says the author of an online article published in 2005. The Uberman Sleep Schedule became somewhat popular among its followers, but scientists knew little about its long-term effects, and some of these experts referred to the concept as a “potentially dangerous way to increase [one’s] waking hours."
More recently, investigators for a study published just last year (2021) in the journal Sleep Health state emphatically that they “found no evidence supporting benefits from following polyphasic sleep schedules.” Based on their findings, “the consensus opinion is that polyphasic sleep schedules, and the sleep deficiency inherent in those schedules, are associated with a variety of adverse physical health, mental health, and performance outcomes. Striving to adopt a schedule that significantly reduces the amount of sleep per 24 hours and/or fragments sleep into multiple episodes throughout the 24-hour day is not recommended,” they write.
Phasic Sleep Pattern Might Be Indicator of Disorders
For some people, polyphasic sleeping patterns may indicate the presence of an underlying disorder, like Alzheimer’s disease; irregular sleep-wake syndrome in which a person falls asleep and wakes up at scattered intervals because of abnormalities in his/her circadian rhythm; or insomnia, defined by the American Academy of Sleep Medicine as “persistent difficulty with sleep initiation, duration, consolidation, or quality.”
Indeed, modern medicine advises a controlled amount of bedtime—a kind of sleep segmentation—for patients with insomnia. Sleep restriction can benefit insomnia patients by consolidating their sleep and improving their sleep efficiency. Experts state that normal sleep efficiency should be about 85 percent of the total hours spent lying in bed. Too much time in bed while not sleeping may actually promote—or exacerbate—insomnia. The cognitive behavioral therapy procedure, developed by psychologist Arthur Spielman, eliminates prolonged middle-of-the-night awakenings for insomniacs by restricting the time they spend in bed. That restriction is then gradually eased.
However, doctors also warn too much “sleep restriction” is not healthy either. The Centers for Disease Control and Prevention report that one in three adults in the United States are chronically sleep-deprived.
And Should You Awake in the Middle of the Night…
The upshot of this discussion: Sleep patterns are not necessarily as crucial as sleep hours. Both the American Academy of Sleep Medicine and the Sleep Research Society recommend most adults between 18 and 60 years of age sleep a minimum of seven hours daily to maintain a healthy lifestyle. Neither organization specifies how one achieves those hours. Remember, seven or eight is a recommendation—not a mandate. Trying to force sleep because “I must get those hours in” can lead to a vicious cycle of anxiety, hyperarousal, and eventually insomnia.
And, if you awake in the middle of the night with no interest in arising and putting another log on the fire, chatting with a spouse, or calling a friend, and have an ardent desire to return to sleep as quickly as possible, here are several tips:
- Engage in slow, deep breathing to stimulate the parasympathetic nervous system or try “box breathing” in which one inhales slowly, holds the breath in, and then slowly exhales.
- Do a few relaxation exercises by progressively tensing and relaxing body muscles, starting with the feet.
- Consider learning mindfulness meditation techniques.
- Stop looking at the clock on the nightstand. It will not help you return to sleep but only increase anxiety.
- If you cannot return to sleep within approximately 20 minutes, get out of bed, go read a book or do something else relaxing until feeling sleepy again.
- Finally, prevent the risk of middle-of-the-night wakefulness in the first place by cutting off the use of electronic devices an hour before retiring; avoiding consumption of caffeine, alcohol, and big meals close to bedtime; exercising and following a healthy diet during the day; and keeping the bedroom cool and dark. Even a small nightlight can negatively affect sleep consolidation and efficiency.
Indeed, it may have been for those middle-of-the-night insomniacs and biphasic or polyphasic sleepers, that Victor Hugo, author of Les Miserables, wrote this simple truth: “Sleep comes more easily than it returns."
