When trying to get enough sleep, it’s natural to be preoccupied with the number of hours in a night. Although sleep time is critical, it is not the sole factor.
Consider the quality of your sleep and whether the time you spend in bed is genuinely restorative when deciding how much sleep you need. Getting the best night’s sleep necessitates moving through the four stages of the sleep cycle as smoothly as possible.
Each stage of sleep is essential for a rested mind and body the next day. Insomnia and obstructive sleep apnea are only two of the many sleep disorders that can have negative effects on a person’s health and ability to sleep.
What Is the Sleep Cycle?
Sleep is not always the same. As a result, your night’s sleep consists of numerous cycles of the sleep cycle, each of which consists of four distinct stages of sleep. Every night, a person sleeps four to six times. The typical length of a person’s sleep cycle is approximately 90 minutes.
Are All Sleep Cycles the Same?
As you proceed through your nighttime sleep, it is natural for your sleep cycles to shift. It is common for the initial sleep cycle to last between 70 and 100 minutes, while subsequent cycles tend to be between 90 and 120 minutes long. Each cycle also alters as the night progresses, in terms of the amount of time spent in each stage of sleep.
A wide range of factors, such as age, previous sleep patterns, and alcohol intake, can influence a person’s sleep cycle.
What Are the Sleep Stages?
A rapid eye movement (REM) sleep stage and three non-REM sleep stages make up the four stages of sleep. Analyses of the brain’s activity while you sleep reveal specific patterns that define each of these stages.
Stage 1 of the sleep cycle
- NREM is the most common form of sleep.
- One of the more commonly known names is N1.
- A typical length of 1 to 5 minutes is considered normal.
Stage 2 of the stages of sleep
- NREM is the most common form of sleep.
- Other names: N2
- A typical length of 10-60 minutes is considered normal.
Stage 3 of the sleep cycle
- NREM is the most common form of sleep.
- Another name for this state is “Deep Sleep,” which is short for “Slow Wave Sleep.”
- A typical length of 20 to 40 minutes is considered normal.
Stage 4 of the sleep cycle
- Restless Legs Syndrome (RLS)
- Respiratory Emphysema Sleep
- A typical length of 10-60 minutes is considered normal.
It is usual to refer to sleep architecture as a breakdown of a person’s sleep into several stages and cycles. A hypnogram, a visual representation of the sleep architecture, can be obtained by a sleep study.
The American Academy of Sleep Medicine revised their definition of sleep phases in 2007 and it became effective in 2008. (AASM). Until then, the majority of specialists referred to the sleep cycle in terms of five distinct stages, but the AASM’s four-stage definitions have since come to represent the majority view.
NREM Sleep Patterns
Non-rapid eye movement sleep (NREM) consists of three distinct stages. The more advanced a person’s NREM sleep is, the more difficult it is to wake them from slumber.
Stage 1 / N1
This is the “dozing off” stage, which lasts anywhere from one to five minutes, depending on the individual.
In N1 sleep, the body is still tense, but the body and brain’s activity begin to slow down (twitches). In this stage of sleep, the brain’s activity begins to shift in a subtle way.
The first stage of sleep is the easiest to interrupt, but if a person is left alone, they can easily move on to the second stage. Uninterrupted sleepers, on the other hand, may not spend much time in stage 1 during the night.
Stage 2 / N2
Stage 2 is characterized by a decrease in body temperature, a relaxation of muscles, and a slowing of both respiration and heart rate. Eye movement stops as well as a new pattern of brain waves emerges. Even if the overall rate of brain activity decreases, the brain does have brief spurts of activity that aid in fending off external stimuli.
First-cycle Stage 2 sleep can last anywhere from 10 to 25 minutes, and each subsequent N2 stage can get longer. N2 sleep accounts for approximately half of a person’s total sleep time.
Stage 3 / N3
Those in stage 3 sleep, often known as profound slumber, are more difficult to awaken from. During N3 sleep, when the body relaxes even more, the heart rate, pulse, and breathing rate all decrease.
Delta waves, a pattern in brain activity that can be observed over this time period, can be identified. For this reason, delta sleep or slow-wave sleep may be referred to as stage 3. (SWS).
Restorative sleep is thought to be impossible without this stage, according to experts. The immune system and other important biological functions may be strengthened as a result. There is evidence that deep sleep benefits to insightful thinking, creativity, and memory, even when brain activity is reduced.
During the first half of the night, we spend the most time in a deep sleep mode. N3 phases typically last between 20 and 40 minutes in the early stages of sleep. As you sleep longer, these stages become shorter, and you spend more time in rapid eye movement (REM) sleep.
REM Sleep Patterns
During REM sleep, brain activity increases to levels comparable to those experienced while awake. There are two exceptions to this transient muscle paralysis: the eyes and the muscles that govern respiration. The body goes through atonia during this time. Although the eyes are closed, it is possible to see the rapid movement of the pupils, hence the name of this stage.
Memory, learning, and creativity are all attributed to rapid eye movement (REM) sleep. The considerable increase in brain activity during REM sleep is thought to be the cause of the most vivid dreams. During REM sleep, dreams are more common and strong, whereas during NREM sleep they are less common and less intense.
Normally, you don’t reach REM sleep until about 90 minutes into your sleep cycle. REM stages become longer as the night progresses, particularly in the latter portion of the night. In contrast to the first few minutes of REM, later stages can span an hour or more. Adults sleep around a quarter of the time in REM periods.
What Does A Normal Night Look Like?
The length of time spent in each stage of sleep varies greatly from one night to the next and from one person to the next. To get the most out of your night’s sleep, it’s recommended that you have four to five 90-minute cycles, which allow your body to cycle through various stages of sleep.
There are four distinct stages of sleep: waking, light sleep, REM, and repeat. Generally each cycle proceeds progressively through these stages: REM sleep is more prevalent later in the night, but deep sleep is more prevalent earlier in the night. During the final cycle, your body may even decide to forego deep sleep entirely.
The bulk of the night, your body is in a state of light slumber. It’s impossible to predict how long you’ll spend in REM or deep sleep, but below are averages for each stage.
Facts about sleep
Despite the importance of sleep to our physical and mental well-being, there is still a lot we don’t understand about it. The following are seven interesting facts that we are aware of:
- Humans sleep for around a third of their lives, compared to cats who sleep for about two-thirds of their lives. There are certain creatures that can sleep for up to 22 hours each day.
- Infants and toddlers need 14 to 17 hours of sleep a day, whereas adolescents need 8 to 10 hours. A typical night’s sleep for an adult is between seven and nine hours.
- Insufficient sleep can have a devastating effect on one’s overall health. Even 24 hours of sleep deprivation can have a substantial impact on mood, ability to function, and perception.
- At 12-2 p.m. and 8-9 p.m., our energy levels normally decline. This helps to explain the mid-afternoon weariness that some people experience after eating lunch.
- The quality of one’s sleep may be harmed by living at higher elevations. This may be due to a lack of slow-wave (deep) sleep, according to research from reputable sources.
- The most important thing we know about sleep is that it is equally as important to good health as nutrition and exercise.
The sequence of Sleep Stages
It’s crucial to understand that the stages of sleep do not occur in chronological order.
It goes like this when you’ve had a full night’s sleep unbroken;
- Stage 1 of the NREM sleep cycle is where sleep begins.
- Progresses from NREM stage 1 to NREM stage 2
- The third stage of NREM is immediately following NREM stage 2.
- The second stage of NREM is then performed once more.
- You’ve made it to REM slumber at long last.
The body normally returns to NREM stage 2 after REM sleep is over before starting the cycle all over again.
As the night progresses, the amount of time spent in each stage shifts (about four to five times total).
A person’s sleep architecture relates to their nightly cycles and stages. A hypnogram, which is a graph generated by an EEG, may be used by a sleep specialist to show you this information.
Why Do the Sleep Stages Matter?
As the brain and body recoup and develop, sleep stages are critical. Some of the significant implications of insufficient sleep on thinking, emotions, and physical health may be explained by a lack of both deep sleep and REM sleep.
People with sleep apnea, for example, may find it difficult to go into deeper sleep stages if they are regularly awakened up in the early stages of sleep. There may not be enough overall sleep time to accrue the required time in each stage of sleep for people who suffer from insomnia.
What Can Interrupt Your Cycle
The term “interrupted sleep” is used to describe a night of sleep that is interrupted. You may find yourself unable to fall asleep if this occurs. A sleep cycle may be interrupted and restarted before it is complete.
Disruptions to your sleep patterns can be caused by a wide range of factors. This can happen just on rare occasions or on a regular basis, depending on the underlying cause.
Interrupted sleep can be caused by a variety of circumstances, some of which are listed below.
- It’s a sign of age: You will find it easier to get out of bed in the morning.
- Frequent urination during the night, or nocturia.
- An increasing number of people are suffering from sleep problems such as restless leg syndrome (RLS), which causes the legs to jerk uncontrollably while the patient is asleep (a strong sensation of needing to move the legs)
- As a result of fibromyalgia and other forms of long-term or acute pain, many people have trouble sleeping or staying asleep.
- Depression and bipolar disorder are examples of mood disorders.
- Alzheimer’s disease, Parkinson’s disease, obesity, heart disease, and asthma are only a few examples of other health concerns.
- Exercise, smoking, excessive coffee consumption, and drinking excessive amounts of alcohol are only few of the lifestyle habits that contribute to obesity.
The American Academy of Sleep Medicine estimates that around 70 million Americans have a sleep disturbance each year. As a result of a poor night’s sleep, one may suffer from a variety of health issues. Sleep problems and the methods used to treat them are described in the following sections.
An inability to sleep is the primary symptom of insomnia. Some people find it difficult to fall asleep, while others find it difficult to stay asleep. Excessive daytime sleepiness and exhaustion are common side effects of insomnia.
Insomnia is best treated with cognitive behavioral therapy. Additionally, sleep medicines can be used to help people fall and stay asleep while doing CBT. Improving one’s sleeping habits may also be beneficial for certain people.
People with obstructed airways during sleep, or OSA, experience episodes of pauses in breathing while they sleep. Apnea, the medical term for these times of not breathing, occurs when the airways in the throat become too narrow to allow for enough airflow. The quality of one’s sleep can suffer as a result of this disorder.
Continuous positive airway pressure (CPAP) is the primary line of treatment for OSA. A person with sleep apnea can breathe normally at night thanks to the CPAP’s powerful airflow.
There may be an alternative to the CPAP if it doesn’t help: bilevel positive airway pressure (BiPAP, also known as BPAP). OSA may necessitate an oral appliance or surgery in some situations.
Shop Healthline-approved snoring and sleep apnea products in our sleep shop.
Restless leg syndrome
Repetitive leg movements (RLMs) are the result of a neurological illness known as restless leg syndrome (RLS). RLS typically happens at night as the individual prepares for sleep and when the individual is in bed relaxing or trying to sleep. RLS sufferers frequently find it difficult to get a good night’s sleep due of their symptoms.
RLS symptoms can be treated using FDA-approved medicines. Relaxing the body before bed and making it simpler to fall asleep can both be achieved by following proper sleep hygiene practices.
Shift work disorder
Working outside of a 9-to-5 schedule might lead to a disease called shift work disorder. The natural sleep-wake cycle can be disrupted by this disease. People who suffer from this illness are more likely to suffer from daytime sleepiness and other health problems than those who do not.
When it comes to treating shift work disorder, it’s important to nap strategically, avoid stimulants like light, and reduce the number of hours you work. It’s also a good idea to use light-blocking drapes or eye shades if you plan on sleeping throughout the day.
“Sleep attacks” and poor nighttime sleep are symptoms of narcolepsy, a chronic central nervous system illness. Sudden physical collapse brought on by loss of muscle control is also common in people with type I narcolepsy.
As a result, people with narcolepsy types I and II frequently undergo major life changes.
Narcolepsy is treated with medications such as stimulants and SSRIs. Practicing proper sleep hygiene, diet, and regular exercise at home will help you get a decent night’s sleep.
When you have narcolepsy, it might be difficult to deal with. Taking strategically timed naps may be beneficial to your health. Narcolepsy sufferers and their loved ones can benefit from support groups and counseling.
Tips to get quality sleep
The greatest strategy to achieve a good night’s sleep is to practice good sleep hygiene. To improve your sleep hygiene, here are a few tips:
- Spend as much time as possible during the daytime hours exposed to the sun. Your body’s circadian rhythm is affected by exposure to natural light during the day.
- Engage in some form of physical activity every hour of the day. Getting at least one exercise or movement activity in each day will help you sleep better.
- Do not sleep for more than 20-30 minutes at a time. There are several advantages to taking a nap. For those who sleep longer than 30 minutes, they risk being awakened when it’s time for bed.
- Take care not to eat or drink anything that will keep you awake before bedtime. Sleep disturbances can be caused by ingesting meals that upset your stomach or contain stimulants such as caffeine, nicotine, or alcohol just before going to bed.
- Limit your screen usage one hour before you go to sleep. It has been shown that the hormones that help you sleep are disrupted by blue light, which is emitted by electronic gadgets like TVs, phones, and more.
- Create a relaxing atmosphere in your bedroom. An investment in high-quality bedding (such as a mattress, pillow, blanket, and so on) can help you sleep more soundly.
- Do you need some ideas? Check out our market for recommendations on pillows and mattresses, all of which have been approved by our editors and experts.
These suggestions, if implemented gradually, will have a significant impact on the quality of your sleep. The doctor may be able to give you other options if you’re still having difficulties falling or staying asleep.
How Can You Have a Healthier Sleep Cycle?
Even if you don’t have complete control over your sleep cycle, there are things you can do to increase the likelihood of a smooth transition from one stage of sleep to the next.
It’s critical to work on sleep hygiene, which includes finding the ideal mattress, pillows, and linens, as well as developing better sleep habits. Your circadian rhythm can be properly aligned if you obtain enough sleep, avoid alcohol before going to bed, avoid light or noise before going to sleep, and keep your sleep routine constant.
A doctor who specializes in sleep disorders like sleep apnea should be your first stop if you’re experiencing extreme daytime sleepiness or suspect that you may have a sleep condition of some sort. It is possible to have a better night’s sleep if you address the root causes of your insomnia.
FREQUENTLY ASKED QUESTIONS
What is rapid eye movement sleep?
The fourth stage of sleep is known as rapid eye movement (REM) sleep. Brain activity increases to a level equivalent to when you’re awake, resulting in vivid dreams at this stage. When we’re dreaming, our brains temporarily paralyze our primary muscles, making it impossible for us to move.
How much REM sleep do you need?
The amount of REM sleep required is not predetermined. This is because REM occurs in short bursts at irregular times during the sleep cycle. It is recommended that most people receive between seven and nine hours of sleep each night, however this can vary from person to person.
How long is each sleep stage?
- After falling asleep, NREM stage 1 lasts less than 10 minutes.
- Stage 2 of the NREM sleep-wake cycle lasts 30 to 60 minutes.
- Stage 3 of NREM sleep: 20-40 minutes
- 14 hours of REM sleep: The first sleep cycle lasts around ten minutes, and subsequent ones go longer and longer.
How long is a sleep cycle?
Around 90 to 110 minutes is the typical length of a complete sleep cycle. As soon as we finish one sleep cycle, the process repeats itself until we wake up.