Sleep Cycles, Stages, and REM Explained

Sleep Cycles, Stages, and REM Explained


5 minute read

Sleep is important for health and functioning, but you may be surprised to learn that there is more to a night of sleep than simply lying down and falling into a deep slumber. This is because your night is divided into various sleep cycles, each of which plays a different role in restoring the brain and body.

What Are The Different Sleep Cycles?

Throughout the course of the night, the body passes through four different sleep cycles or stages and repeats these cycles several times:

  • Stage 1: During stage 1, the body transitions from wakefulness to sleep. This stage lasts only a few minutes, and during this light phase of sleep, the brain waves, heart rate, and breathing rate begin to slow. The muscles also relax and may twitch from time-to-time.
  • Stage 2: Stage 2 sleep is also a light sleep stage, during which the muscles relax further, and the body temperature lowers.
  • Stage 3: This is the deepest sleep stage, during which the heart rate and breathing rate are at their lowest levels, and it might be difficult to wake someone. This deep stage of sleep is what makes you feel rested in the morning, and it tends to last longer during the earlier part of the night.
  • REM: REM sleep is characterized by fast movement of the eyes, as well as increased brain activity and irregular breathing. During this stage of sleep, the heart rate also quickens. Most dreaming occurs during REM sleep, and the first REM cycle of the night tends to begin about 90 minutes after a person falls asleep. Scientists believe that REM sleep is important for consolidating memories, especially those that are emotional in nature. Getting adequate REM sleep can even help people to regulate their emotions and may reduce the intensity of distressing memories or situations.

The first three stages of sleep are all classified as non-REM sleep.

How Long Do Sleep Cycles Last?

According to Harvard University, a full sleep cycle, in which a person progresses from Stage 1 all the way through REM sleep, lasts about 70 to 100 minutes at the start of the night, but closer to 90 to 120 minutes later in the night. Scientists have been able to determine the length of sleep cycles by using EEGs and other medical equipment to study brain waves during sleep.

Healthy sleep cycles in adults typically begin with non-REM sleep. The process starts with Stage 1 sleep, which lasts for only one to seven minutes and then progresses into Stage 2 sleep, which usually lasts between 10 and 25 minutes. Next, the body moves into deep Stage 3 sleep and spends 20-40 minutes in this sleep stage. The sleep cycle continues with a person transitioning back to the lighter Stage 2 of sleep for a few minutes, before entering an REM sleep phase, which makes up around a quarter of a person’s total sleep time.

While there are some expected durations for the various sleep stages, sleep cycles times can differ from person-to-person. For instance, infants usually begin sleep in REM stage, instead of starting with non-REM sleep, and their sleep cycles are shorter, at 50 to 60 minutes each. Young children also spend more time than adults do in deep sleep.

Poor sleep habits can also alter sleep cycles. Adults who are sleep-deprived or who have had an inconsistent sleep schedule may spend more time in deep sleep when compared to those with healthy sleep cycles.

Promoting Healthy Sleep Cycles

If you struggle with feelings of tiredness, you may not be getting adequate sleep. You could be missing out on restorative Stage 3 sleep, or perhaps you are not getting enough REM sleep to regulate your emotions. If this is the case, there are things you can do to promote healthy sleep cycles.

For example, it is important to keep a consistent sleep schedule, so that your body develops a pattern and can more easily fall asleep and stay asleep throughout the night to progress through all needed sleep stages. You may also consider getting more exercise, as physical activity can improve sleep.

Some home remedies for insomnia, such as deep breathing, magnesium supplements, and limiting caffeine can also be helpful if you’re having trouble falling asleep and staying asleep throughout the night. If you struggle to fall asleep, a comforting weighted blanket can make it easier for you to drift off at night.

Sleep Better with Aricove

Waking frequently throughout the night can make it difficult to progress through each stage of sleep and get the deep sleep and REM sleep you need to feel and perform your best. For those who have trouble sleeping, a weighted blanket can help.

Aricove offers a variety of blanket weights to meet each person’s needs. When choosing a weighted blanket, a general rule of thumb is to select a blanket that is about 10 percent of your body weight, but people with sensitive joints or hip pain may need a lighter blanket. That being said, following the general rule of thumb, a 10 lb weighted blanket is suitable for smaller adults, who weigh in at around 125 lbs or less, whereas heavier versions of 20 lbs will suit those who weigh 200 lbs and up.

Regardless of the size you need, the comfort provided by Aricove’s bamboo weighted blanket is sure to make for a better night of sleep, as the luxurious fabric is naturally soft and wicks moisture away from the body to keep you cool and help you sleep soundly for the duration of the night.

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