It's common to focus on your total number of hours of sleep when considering whether you're getting the rest you need. While the length of sleep is certainly significant, it is not the sole factor to consider. Your mind and body can awaken feeling rested thanks to each sleep cycle. Your body and brain are working hard to absorb the day that just passed and prepare for the one that lies ahead while you sleep. Did you know your brain goes through four separate phases of sleep a total of five or six times before you wake up? That is if you get the recommended seven to nine hours of sleep each night. And we all know you’re doing that, right?
And when we don't get enough quality sleep, it affects us in many ways. Lack of sleep impairs cognitive abilities like memory, focus, and mood. Additionally, it can lead to health issues like hypertension and heart disease. It may also increase the risk of injury, such as car crashes. If you want more restful sleep, keep reading to understand your sleep cycle and how to unlock new levels of restoration.
What Is the Sleep Cycle?
When you sleep, your brain and body go through a series of changes. These changes are referred to as your sleep cycle, and each stage of sleep has different effects on your mind and body. The sleep cycle is made up of four stages of non-REM (NREM) sleep and one stage of REM (rapid eye movement) sleep.
NREM sleep is often referred to as quiet sleep. The first three sleep cycle stages are NREM sleep, and they progress from light to deep sleep. REM sleep is when you dream, and your brain is more active during this stage than any other stage of the sleep cycle. You know all about brain activity during REM from those crazy dreams that make no sense!
The time someone spends in each stage varies from person to person, but a typical sleep cycle lasts around 90 minutes. People usually spend more time in NREM sleep at the beginning of the night and more time in REM sleep toward the end of the night.
What Are the Stages of Sleep?
Now that you know what it is, it's time to take a closer look at the different stages of sleep.
Stage 1: N1 Sleep
N1 sleep is the lightest stage of sleep. It's very simple to wake someone up during this stage of sleep, and if they aren't bothered, they can easily transition into stage 2 of sleep. This stage generally lasts for one to five minutes.
During N1 sleep, your eye movement slows, and your muscles begin to relax. You may experience hypnagogic jerks, which are sudden muscle contractions that can cause you to feel like you're falling. Yep, we all know the feeling.
Stage 2: N2 Sleep
N2 sleep is a deeper stage of sleep than N1 sleep. During this stage, your eye movement stops, and your brainwaves become slower. This stage lasts for 10 to 25 minutes.
During N2 sleep, your body temperature begins to drop, and your heart rate slows. You may experience brief bursts of brain activity that can help you to not wake so easily. This stage of sleep is the primary stage you'll spend most of your sleep time.
Stage 3: N3 Sleep
N3 sleep is the deepest stage of NREM sleep. This stage is also known as slow-wave sleep or delta sleep. During this stage, your muscle tone, pulse, and breathing rate decrease. This stage commonly lasts for 20 to 40 minutes.
N3 sleep is critical to restorative sleep, allowing for bodily recovery and growth. It may also bolster the immune system and other key bodily processes. We spend the most time in N3 sleep during the first half of the night. As you continue sleeping, these stages get shorter, and more time gets spent in REM sleep instead.
REM sleep is the final stage of the sleep cycle. The degree of brain activity increases during REM sleep and approaches that of awakeness. The muscles in the body temporarily paralyze at the same time, apart from the muscles that control breathing and the eyes. The name for this stage comes from the fact that although the eyelids are closed, they can be seen moving fast. REM sleep is essential for cognitive processes like memory, learning, and creativity.
In a typical sleep cycle, you don't reach an REM sleep stage until after roughly 90 minutes of sleep. REM periods lengthen during the night, but especially in the second half. The first stage of REM sleep may only last a few minutes, while later stages might endure for up to an hour.
Fun fact: adults spend about 25% of their overall sleep time in REM periods.
Why Do the Sleep Stages Matter?
The stages of sleep are important because they enable the body and brain to recover and thrive. Some of the severe effects of inadequate sleep on thinking, emotions, and physical health may be explained by failing to get enough deep sleep (REM sleep).
People who regularly wake up during the earlier stages of sleep, such as those with sleep apnea, may find it difficult to cycle into deeper sleep stages. People with insomnia might not receive enough sleep overall to complete each step in the necessary time.
How To Get Better Sleep
Even though you don't have complete control over your sleep cycle, you can take measures to increase the likelihood that you will move through each stage of sleep in a healthier way.
A crucial first step is to improve your sleep hygiene, including your sleep necessities (mattress, pillows, and sheets) and sleeping routines. You can enjoy undisturbed sleep and support optimal circadian rhythm alignment by establishing a more regular sleep schedule, getting natural sunshine exposure, avoiding alcohol before bed, and removing noise and light disturbances.
You should consult a doctor who can provide you with the necessary direction if you find that you are excessively sleepy during the day or think you could have a sleep disorder. Achieving more thorough and restorative sleep cycles can be assisted by addressing underlying concerns.
If you think your mattress impacts your sleep, you may want to consider getting a new one. Crane's Mattress has just what you need. Whether you sleep hot or cold, on your back or side, or desire extra firm or ultra-plush, we have it all. Give our experts a call if you have any questions; we would be happy to help you!