The Phases of Sleep for Adolescents

The sleep cycles in children and adolescents should involve various phases or stages. Rest is important for them at their stage of development.
The Phases of Sleep for Adolescents

Last update: 25 May, 2019

Getting enough regenerative sleep is one of the most fundamental requirements for adequate brain development in adolescents. It’s common for young people to underestimate the importance of getting the right amount of rest recommended for a balanced life. Thus, the phases of sleep for adolescents are essential.

Being young and full of vitality makes it easy for teenagers to mask fatigue and a lack of sleep. Nonetheless, an adequate amount of quality sleep is necessary and indispensable for adolescents; especially considering that each of the 5 phases is regenerative and furthers their mental, emotional, and physiological development at this stage of life in different ways.

Furthermore, the amount of rest needed by the body varies depending on the person’s age. Adolescents need more sleep than adults. That’s to say, a young person between the ages of 11 and 17 years old will need at least 9 or 10 hours of sleep a day.

It’s common for adolescents to have difficulty getting up in the morning. This is due to their natural tendency to sleep until all the sleep phase cycles are completed.

Why go through all the adolescent sleep phases

The function of sleep at any age is for the body and mind to repair themselves. By sleeping, your body begins a series of regenerative cellular processes in order to get energy. It’s during sleep that the production of some hormones increases, like the growth hormone. 

On the other hand, there are also mental mechanisms of memory, attention and focus that regenerate while we’re sleeping and that will help adolescents in their intellectual pursuits.

Considering all the factors above, it’s vital that adolescents assure they’re getting the right quality and amount of sleep. Their brain development is still in process.

A lack of proper sleep can have a negative influence on their psychological wellbeing and their physical strength. A lack of sleep affects their academic performance and even their behavior.

The Phases of Sleep for Adolescents

Whereas an adult can control their impulses and emotions in a conscious way, that kind of control is more difficult for adolescents and it’s harder still if they’re fatigued and lacking adequate sleep. Adolescents have their own biological rhythms that are different than those of the adult body and mind.

What are the five stages of sleep for adolescents?

Ever since the pioneering sleep studies conducted by W.C. Dement and N. Kleitman in 1957 using electroencephalograms, sleep cycles have been described in five phases. This research is still relevant today although a few adjustments or precisions have been made given the new technology available.

This research showed that each phase of sleep lasts for around 100 minutes. They also discovered that the five stages repeat in a continuous cycle. The phases begin with a light sleep and then pass into deeper levels of sleep until achieving the REM state, which is also a lighter stage of sleep that prepares the person to wake.

Phases of sleep for adolescents: First phase

Falling asleep or the transition phase accounts for 5% of our total sleep. This transition between being wakeful and falling asleep occurs in every repetition of the cycle. This is the phase known for containing alpha waves, the same brain waves that occur when we relax while wakeful as well.

“Sleep activates a series of regenerative cellular processes that provide us energy; also sleep is when the body produces some hormones like the growth hormone in greater quantities.”

Second phase

This phase is when the disconnection from your surrounding intensifies. This makes it possible for you to enter a gradually deeper sleep. During this phase, physiological activities like muscle movements are lowered.

This stage in the sleep process is still a light sleep that takes place after you first fall asleep. This phase represents about 50% of your total sleep and it’s when the beta brain waves are active.

The Phases of Sleep for Adolescents

Third and fourth phase

These phases represent deep sleep or the delta phase. These phases of sleep are of great importance in adolescence because this is when the body recuperates the most.

Fifth phase

This is the slow sleep phase that occupies 25% of our total sleep. This is the phase where parasomnias or sleep disruptions can occur like sleepwalking, night terrors and bedwetting.

REM phase

This 5th phase is called the “quick waves” phase due to rapid eye movements. This phase of sleep represents 20% total of sleep even though the predominant waves are beta waves – that’s to say, you have left the deep sleep characterized by delta waves. But in this phase, it’s harder to wake up.

Just before waking is when dreams and nightmares take place that are later remembered when you open your eyes. This phase is longer in children. Experts have found this phase essential for optimal brain development.

In summary, it’s important that adolescents get enough sleep so their bodies rest adequately in all these different phases. The sleep phases in adolescents are essential for adequate mental and emotional development. The fact that adolescents sleep more than everyone in the family is a sign of good health.


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This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.