What is a Chronotype?

Chronotype scale in our society based on the results of the MCTQ- questionnaire.

The inner clock works different for every individual. It is a trade of ours like our hight or our haircolour, it is magnificently individual but yet we can measure and classify it.

The relationship of our inner cycles to the day and night cycles of the outside world is what we describe in Chronotypes (gr.Chronos = time).

The fact that every person has an individual Chronotype is easy to spot.

We tend to feel tired or awake every day at the same time of the day.

We have cognitive peak phases throughout the day where we seem to absorb information particularly well, and other times where everything else around us seems to be more interesting then the task at hand.

If we take a look at these times and compare them to the times and phases of our partner, friends or working colleagues we’ll notice that they can vary quite significantly from person to person.

A good example for this is our start to the day. When we measure the activity levels of people early in the morning, we get an idea of how much our chrono type impacts our behavior.You might be someone who wakes up in the morning at 5 pm, starts the day with a run or a swim, feeling active and awake early in the morning, while your partner snoozes until the very last minute and even then hardly gets his/her foot out of the bed, not feeling awake until noon.When the sun sets however, you begin to yawn and your body starts feeling heavy at 10 pm, while your partner stays awake until 1 am in the morning, studying/drawing/reading/watching TV.

Exactly those times when we naturally feel awake or tired give away our Chrono-type and we can calculate the median point of our sleep phase. For example with a sleep phase from 11pm to 8 am, the median point of sleep is at 4:30 am. In national comparison this is an average Chronotype or “Norm – type”. Our society has a wide range of Chronotypes where the early and late types set the extremes to both sides of the scale. Judging someones chronotype is like judging someones hight. If you are 175 cm tall, you’d be considered a tall person in the phillipines, whereas in Holland where the average hight is 183cm you’ll feel small. There is no definiton of when a person is considered tall or small – it is always relative to the environment. Chronotypes act exactly the same way, and if you happen to be a later type then the “Norm-type”, you might find yourself judged a “sleepy head” by the majority of society.

Altersabhängige Entwicklung des Chronotyps
The natural median point of sleep (without alarm clock) describes the chronotype.

innere Uhr von frühen Chronotypen eine Eigenperiode die etwas kürzer ist als 24 Stunden. Deshalb werden Frühtypen früher am Abend müde und wachen morgens früh ohne Wecker auf. Späte Chronotypen werden im Vergleich dazu später müde und schlafen weiter in den Tag hinein. Ihre innere Uhr hat eine Periode die länger als 24 Stunden ist. Sie benötigen zudem meist einen Wecker um morgens pünktlich bei der Arbeit zu sein. Die Bedeutung des Chronotyps besteht nun darin, dass dieser ein idealer, einfach zu bestimmender Marker für die innere Uhr eines Menschen ist. Die Innenzeit eines Menschen, bestimmt durch die individuelle innere Uhr, hat nämlich eine große Bedeutung für die Wissenschaft und Medizin. Dies kommt besonders im Rahmen der gesundheitlichen Probleme von Schichtarbeitern zum Tragen.

Wichtig ist dabei auch zu wissen, dass sich der Chronotyp im Laufe eines Lebens verändert. Seinen Peak (späteste Schlafmitte) erreicht der Mann mit einem Alter von ca. 20,9 Jahren und die Frau mit einem Alter von ca. 19,5 Jahren.