By now everyone should know that sleep is essential for our mental and physical recovery. At night, our brain processes the things we have experienced during the day and stores important information in our long-term memory. But what are the different sleep phases we go through at night and which are most important for our body?
It’s definitely worthwhile to take time to familiarize yourself with your sleep cycle, because your body does different things while you’re asleep, which can be divided into five different phases. Ideally, we should be able to improve our sleep by better understanding the importance of these sleep phases and how our bodies recharge their batteries while we sleep.
The five sleep phases
Good and restful sleep means that the five sleep phases occur uninterruptedly one after the other, and then repeat themselves several times per night in a 90-minute cycle. In total, we go through about four to seven of these cycles per night, though of course this obviously depends on how long we sleep.
If we’re sleep deprived or our sleep is interrupted, our brains can’t process the information it’s taken in throughout the day; this has a negative effect on our learning. That said, sleep deprivation not only affects our ability to learn, but also our performance. Researchers have found for example that you can’t recover from a sleep deficit by sleeping in on the weekends, due in part to the sleep phases we go through at night.
The first sleep phase - falling asleep
The fall asleep phase is, of course, the phase just before and after falling asleep. In this phase, our brain shuts down much of its activity and our muscles start to relax. If the brain shuts down faster than our muscles, we can experience muscle twitching or a feeling of falling.
How long does it take us to fall asleep on average? According to a forsa survey commissioned by Techniker Krankenkasse in 2017, around 44% of respondents answered that it takes between eleven and thirty minutes to fall asleep. 41% of respondents can fall asleep within ten minutes.
Since our sleep is still very light and superficial in this phase, noises from outside can easily wake us up.
The second sleep phase - the light sleep phase
The falling asleep phase is followed by the light sleep phase, in which our muscles relax even more. Our breathing slows down and our pulse rate slowly decreases. The heart rate goes down and our body temperature drops slightly.
We remain in this sleep phase for about thirty to sixty minutes. It takes up the majority of our sleep cycle. During this phase, we begin to process the day’s events. Just like in the falling asleep phase, we can be woken up by slight disturbances.
The third and fourth sleep phase - The deep sleep phase.
Our body and brain can recover the most in the deep sleep phase, which is why the deep sleep phase is the most important of the sleep phases that our body goes through. This phase is usually divided into two phases, namely a phase of medium to deep sleep and a phase of very deep sleep.
It’s not easy for the outside world to roust us from this stage, as we sleep particularly soundly here. If we do wake up, it takes a while before we understand what’s happening around us. Some people may sleepwalk or talk in their sleep during this phase. About 30% of children and 1% of adults sleepwalk during the night.
As our breathing slows down and becomes more rhythmic, the body can reach a state of deepest relaxation here. This phase is therefore essential for healthy and restful sleep.
The fifth sleep phase - dream sleep
After the deep sleep phase, our body enters a light sleep phase again and then the dream phase. This phase is also known as the REM phase (rapid eye movement), because this is when our eyes move fastest under closed eyelids.
However, dreams can occur not only in the dream sleep phase, but also before it. In this phase, however, dreams are the longest and most intense. Researchers assume that we mainly process emotional impressions in the dream phase. In the dream phase, our heart rate increases again and we breathe a little faster, but our muscles remain almost completely motionless.
If our muscles remain active in the dream phase, it’s possible for us to actually carry out the movements seen in our dreams. The body protects us from this by releasing chemicals that paralyze our muscles, except for our eyes, which continue to move.
How long our sleep stages last
Each sleep phase has its own duration.
- Fall asleep phase: 4-5%
- Light sleep phase: 45-55%
- Deep sleep phase deep sleep: 4-6%
- Deep sleep very deep sleep: 12-15%
- Dream sleep phase: 20-25%
These cycles are repeated several times per night; in the first half of the night, deep sleep predominates, while REM sleep is more frequent in the second half and in the morning hours.
Baby sleep phases
Now we’ve looked at the sleep phases of adults, let's now take a look at the sleep phases of babies. Why is sleep so important for babies? Healthy sleep helps babies to develop and grow faster. And not only their bodies, but their brains also grow rapidly while they sleep.
Just like adults, babies go through the REM and non-REM phases of sleep. However, these phases are distributed differently in children’s sleep. For example, babies remain in the dream phase for about a third of the time, while this only accounts for 25% of adult sleep. In newborns, this figure is much higher.
Depending on their age, babies spend about 50% or more of their sleep in the non-REM phase. The falling asleep, light sleep and deep sleep phases I&II are not yet mature in babies from the beginning. This only happens from around the 6th month. As babies spend most of their time in a light sleep phase, they often cry in their sleep and wake up frequently. However, this is completely healthy for them and is a normal part of their development.
Infant sleep phases
Toddlers aged two or three usually need eleven to fourteen hours of sleep. They usually need to nap every day, and it's not until the age of four or five that most children can go without one. It's important to remember that every child’s sleep is different and that each child needs different amounts of sleep.
Products at Zizzz that make falling asleep easier
At Zizzz, we have many great products to help you improve the quality of your sleep. We carry down duvets with ethically-sourced down, as well as the matching pillows. Our duvets come in different sizes and can be perfectly adapted to your bed.
Of course, we have also thought of the little ones! We offer children's duvets made of pure virgin wool from sheep raised in the Swiss Alps and the softest organic cotton. These offer your children a particularly pleasant sleeping environment and help them sleep through the night! Your child is less likely to be woken up by cold or heat with our duvets, as they are breathable and help regulate body temperature.