Every process in our body follows a daily cycle and occurs at predetermined intervals. Sometimes the cycle is more than 24 hours, for example, a menstrual cycle in women. In other cases, the cycle is less than 24 hours, for example, REM and non-REM sleep.
Most of the biological rhythms are a 24-hour internal clock and because of it these rhythms are also known as a circadian or a twenty-four hour rhythm. One of the key rhythms is a sleep/wake cycle.
About 16-18 hours is a wake cycle and the rest is a sleep cycle. But when exactly people tend to sleep or wake is different.
All people can be broadly divided into two groups: night owls and larks. It depends on when you tend to stay up and to begin sleeping.
- Owls, larks, and other birds
In a recently published study, it was shown that in addition to night owls and larks, there are also have at least two other types of people.
These people have not yet been given nice names. Scientists call them highly energetic people. These people are lucky because they are full of energy both in the morning and at night.
The second type of people is quite contrary to the first one. According to the studies, these people behave like night owls in the morning and like early birds at night.
- Methods for measuring a chronotype
It is easy to understand who are you, a night owl or an early bird, by the following description. You are an early bird if you prefer to wake up early and go to bed early. You are a night owl if you stay up until late at night and wake up late in the morning.
Scientists have developed methods to accurately measure a chronotype. Two factors are important: body temperature and active secretion of melatonin.
These two processes are prerequisites for a sleep. In larks, body temperature is dropping and melatonin is actively produced around 8.00-9.00 p.m. and in night owls around 10.00-11.00 p.m.
- Elderly people are typically early birds
A chronotype is not fixed but it changes during the lifetime of a person. The elder we get the more we tend toward morning. This is a physiological process.
With each new year, our body temperature and melatonin secretion occurs earlier and our desire to sleep shifts towards early night.
Night sleep duration in elderly people is shorter and for this reason, they wake up very early in the morning.
- Urban citizens are primarily night owls
The scientists found out that more early birds are living in the country than in big cities. The morning rhythm is closer to the body’s natural rhythm when people are involved in farming.
High levels of illumination in the cities greatly affect our circadian rhythms and shift them. Actually, our biological rhythms just help us to be flexible and adapt to our life.
- You can change your chronotype
Experts believe that we can reset our own circadian rhythms, but it requires time and patience.
The first thing is to regulate the level of illumination as it tells our body whether it is time to go to bed or to wake up.
There also medications to change the circadian rhythm but it is not recommended to take them unless absolutely necessary.