Your Complete Guide to Sleep Cycles & Schedules

Wondering how to fix your sleep schedule?

You’ve come to the right place, and let’s be clear: you’re not alone. According to one study, 25 percent of people who are healthy sleepers have problems with insomnia at some point. The good news? Out of all those people who developed insomnia, 75 percent were able to recover and eventually, sleep normally. They were able to figure out their sleep schedule. That’s what we’re here to help you do.

To have any sort of discussion about sleep schedules and cycles, we have to first talk about that musical and arcane-sounding term you might remember from high school biology: ”circadian rhythm”.

The Definition of Circadian Rhythm

Circadian rhythms are biological and behavioral adjustments based on a daily cycle. Think of a circadian rhythm as a drum beat you’re playing in concert with the rhythm of the Earth’s rotation as it travels around the sun.

As the sun rises and traces its path across the sky, a person with a circadian rhythm (influenced by the presence or lack of light) will usually order their activities around the sun. Therefore, the body’s mental and physical processes sync up with the light cycle. This is not to say that circadian rhythms are delineated entirely by light. Other environmental and biological factors provide an influence as well.

Researchers have discovered that circadian rhythms are intricately connected to each person’s biological clock. The brain and body dance to an innate rhythm. When you get out of step with your innate rhythm, your sleep schedule is disrupted.

If each person has their own biological clock, and therefore their own rhythm, then individual sleep cycles will differ. Some differ only slightly, others differ dramatically. People have trouble with their rhythm when they try to bend their biological clock to a sleep schedule that doesn’t match their natural inclination. However, human beings can be incredibly good at being flexible.

Monophasic Sleep Schedule

People who adhere to a monophasic schedule get around six to eight hours of sleep each night, and then go about their business during the day without any naps. This is the standard schedule society has drilled into many of us through centuries of daytime activity and nighttime rest. It is by no means the only sleep schedule, but there’s a reason why many monophasic sleepers aim for eight hours of sleep each night.

If you’re a monophasic sleeper and you’re figuring out what time to go to bed—which is typically based on what time you have to wake up for work or school—eight hours of sleep makes sense because of the body’s sleep cycle. A complete sleep cycle equals about 90 minutes, and if you disrupt a cycle, it leaves you feeling groggy. Researchers have determined that five full sleep cycles is optimum, which equals about seven-and-a-half to eight hours of sleep.

Biphasic Sleep

While monophasic is one phase, biphasic is two; therefore, a biphasic sleep schedule is two sleep sessions during a 24-hour period. Often, the biphasic sleeper takes a daily nap, and their primary sleep session is at night. The biphasic sleeper’s biological clock may call for more than 8 hours of sleep, so their daily nap could clock them in at nine to ten hours total. Or, they don’t get as much sleep at night, and they satisfy their needs with a nap during the day.

Biphasic sleepers can also follow split schedules, in which they get three to four hours of sleep per session. If their schedule is flexible enough to allow for it, the biphasic sleeper may thrive on this arrangement.

Polyphasic Sleep Schedules

It might seem strange to those of us who follow monophasic or biphasic schedules, but polyphasic sleepers follow a schedule that looks more like a series of naps than anything else. There’s even a polyphasic society devoted to this practice. Depending on their biological clock and schedule, a polyphasic sleeper could sleep up to six times per day. However abnormal this may seem, there’s evidence that segmented sleep was actually the norm for preindustrial cultures that had no artificial lighting.

Segmented sleepers often customize their own schedule, but there are some pre-established routines people follow.

Everyman Sleep Cycle

One version of the everyman cycle calls for three hours of sleep at night and three 20 minute naps during the day. Another calls for four-and-a-half to six hours at night, and two 20 minute naps. Still another calls for one-and-a-half to two hours, and four 20 minute naps. The longer period of sleep is called “core sleep.”

Whether this satisfies the sleeper’s needs depends on their biological clock. If the everyman sleeper can successfully follow the schedule, it creates free time in their day.

Uberman Sleep Technique

Uberman throws the recommended eight hours — and everyman’s core sleep time — out the window. This extreme technique calls for a 20 minute nap every four hours. It sounds like this wouldn’t satisfy sleep requirements whatsoever, and would be hard to do, but some adherents point to the unconfirmed belief that Leonardo Da Vinci and Nikola Tesla followed this schedule.

Dymaxion Sleep Schedule

Easily the most extreme of the polyphasic regimens, dymaxion calls for a half hour of sleep four times per day. According to the Polyphasic Society, the term “dymaxion” was coined by Buckminster Fuller, and far less than one percent of the world’s population has a biological clock that could accommodate it.

How to Fix Your Current Sleep Schedule

If you’re having trouble sleeping, a new sleep schedule might not necessarily be the answer. Take a look at your habits. Cut out screen-time at least an hour before bed, and take time to relax and mentally unwind before you close your eyes.

One habit that about 20 percent of Americans fall into is drinking to help themselves fall asleep. Alcohol at the end of the day may help you go to sleep faster, but it also usually disrupts your sleep cycle later after your body metabolizes the booze. A rush of energy hits, and suddenly you’re awake. Alcohol can disrupt your REM sleep phase and suppresses melatonin production, effectively throwing a wrench in your sleep schedule.

Additionally, sugar and sleep don’t mix. One study showed sugar interrupts sleep, while another showed that people who don’t sleep enough have higher blood sugar levels. In other words, too much sugar will send you into a spiral that doesn’t allow you to metabolize it while you’re sleeping.

Finally, your body temperature decreases as you’re going to sleep. Try regulating room temperature to between 60 and 67 degrees Fahrenheit to match what your body’s doing. Get the internet’s most comfortable mattress that sleeps cool by allowing airflow through the foam, and your beauty rest will be about as refreshing as it gets.