What does normal sleep look like?
One sleep cycle, different stages
During normal sleep, different sleep stages follow one another. It begins with light sleep, followed by deep sleep, ending in a period of REM sleep. This sequence is called one sleep cycle.
A cycle lasts on average 90 to 120 minutes. Most people go through four to five cycles per night.
The first part of the night is marked by deep sleep. The last hours of the night are characterised by light sleep and an increase in REM sleep.
Most adults get about 50 to 65% light sleep, 15 to 20% deep sleep and 20 to 25% REM sleep during the night. Sleeping deeply all night long is neither possible nor necessary.
Not falling asleep straight away?
-
It is normal not to fall asleep immediately after going to bed. Taking a few minutes to half an hour to fall asleep is nothing to worry about. Often, you don’t even realise when you’ve fallen asleep. It’s also normal to wake up briefly during the night between different stages and cycles.
Why do we sleep?
It is clear that sleep plays an important role in various physical and mental processes. A good night’s sleep contributes in many ways to daily functioning and overall wellbeing.
- Sleep provides rest and recovery, which is essential for the proper functioning of the body.
- Sleep has a strong effect on how the brain functions. A good night’s sleep supports alertness, concentration and memory.
- Sleep is important for emotional wellbeing. Lack of sleep can lead to mood swings, increased irritability and reduced stress resilience.
Sleep as an individual process
The amount of sleep someone needs, the best time for them to sleep, and the structure of their sleep vary greatly from person to person.
Short and long sleepers
Not everyone needs the same amount of sleep per night to function well during the day. Being a short or long sleeper is not a sign of a sleep disorder and does not harm your physical or mental health.
Most people need between 6 and 9 hours of sleep per night. Short sleepers feel rested with 6 hours or less, while long sleepers need 9 hours or more to function well during the day.
Morning and evening types
There are differences in when people sleep best. Some are morning types and others are evening types, though most people’s natural rhythm lies somewhere in between.
Morning people often find it hard to stay up late, but they wake up easily in the morning. Evening people, on the other hand, have difficulty getting up early (because they still feel sleepy) and only become active later in the day.
Age
Age is an important factor that influences both the amount and the quality of sleep.
As we age, deep sleep decreases and light sleep increases. As a result, older people wake up more easily during the night.