Q: Can a person add up all their sleep in a 24-hour period to arrive at a total for that day? For example, 30 minutes here, 1 hour there, 4 hours later, etc.
A: For humans, our best sleep is at night. Some restoration processes in the body and brain only take place at night and while asleep. When one of these conditions is not met, this repair and maintenance is impaired or does not happen at all. From all the research, we also know that our bodily processes steer toward a single big chunk of sleep at night (also called monophasic sleep), as shown in the model explained in Dr. Raymann’s presentation — stay tuned to this website for that video!
If you experience a night of sleep that was too short, you can add some sleep time during the day by taking a nap. But the longest part of your sleep should always be at night.
You might have heard of alternative polyphasic sleep patterns, with names like the “Uberman” sleep schedule (6 to 8 naps of 20 minutes evenly distributed across 24 hours), but they are hard to maintain and go against your sleep biology. They might work for you if don’t need to sync with society’s schedule, but even then it is still considered not optimal.
The human biological clock prefers a single, long sleep during the nighttime, with a nap around 2:00 in the afternoon if needed.
Q: How can I increase REM sleep?
A: The keys are sleep regularity and a solid duration of sleep. The amount of REM sleep increases at the end of the night and is a function of time spent asleep. It seems we first need to sleep off our tiredness (reflected in a lot deep sleep) and, if that dissipates, REM sleep gets more prominent.
Therefore, it’s essential to schedule enough time for sleep at the right time. Keep a consistent bedtime, allowing for 7-8 hours to pass before you need to wake up. The more time you will have before the alarm clock goes off, the more likely it is you will have plenty of REM sleep.
If you’re still feeling easily tired, your scheduled sleep time is likely too short. Try scheduling more time to sleep, with an earlier bedtime and the same wake up time — given that you likely need to wake up at a specific time for your job, kids, or other reasons, wake up time is typically not as flexible.
Some behaviors impact the amount of REM sleep, such as drinking alcohol in the evening. Avoid alcohol after dinner time and have your last drink at least 3 hours before bed. The amount of alcohol you drink makes a difference too, so educate yourself about the alcohol content of different types of beverages. Most people can drink up to 2 units of alcohol with relatively low risk of disrupting their sleep.
Q: The normal cycle is “light sleep” – “deep sleep” – “REM”… But what if I have several “light sleep” – “REM” – “light sleep” – “REM” (missing deep sleep phases)? How would that affect my life, is there any reason for that, and what can be done to get more deep sleep?
A: A lack of deep sleep can make you feel more tired and, by getting more tired, you actually get the signal to catch more sleep. As we age, we also see a gradual decline of the amount of Deep Sleep.
Here are a couple tips to help you get deep sleep: (1) Make sure to expose yourself to plenty of natural light in the morning and during the day, and avoid bright light exposure in the evening. (2) Get your body moving. This can be as simple as remembering to take extra steps throughout the day. The more physically tired you are at the end of the day, the more likely deep sleep is going to happen. Following these 2 tips will help the difference between day (light, moving) and night (dark, more sedentary) become very clear to your brain and body, which strengthens the sleep wake pattern.
Also, note that the sleep cycles depicted in textbooks and in Dr. Raymann’s presentation (going from wake to light to deep to REM, and going to repetitive cycles) is the ideal but not always the reality. In your day-to-day sleep you might see all sorts of different patterns, including going back and forth from one stage to another multiple times.