BIOLOGICAL CLOCK. How long should we sleep? What time should I lie? There is in fact no common answer to all. Each has its own “chronotype” genetically programmed, that is to say the position of sleep in 24 hours. You have to know the if you will take good sleep habits and recover well. In 1986, researchers Jim Horne and Ostberg Olov established questionnaire that establishes this chronotype in twenty questions. You will know if you are early (bed early / early bird) or simply extreme, Vesper (Night Owl / late risers) single or extreme, or neutral. A test used today by the majority of international sleep centers and widely validated.
A biological clock in the brain
” the position of sleep in 24 hours, revealed by the questionnaire is directly correlated to the speed of our internal biological clock “, says Dr. Claude Gronfier, neurobiologist, Inserm, vice president of the francophone Society chronobiology. a physically biological clock located in the brain. specifically in suprachiasmastiques nuclei of the hypothalamus. it will, among other rhythm sleep, sleep time, wake, sleep doors openings (times of the day where one falls asleep easily.)
on average, the period of this clock is 24 h 12. But it can range from 23 hours 30 minutes for the “bed early / Arise early “, which have a slightly faster clock at 24: 30 pm for” night owl / up late “, which have a slightly slower clock.
as a result, if you are born early, you will never be a night owl and may say a “Vesper extreme” early to bed, her biological clock will deny him sleep before a late hour! This is precisely what happens in teenagers whose clock is slowed down at this time of life; they therefore can not fall asleep earlier, whatever we tell them.
The current problem is the mismatch between our chronotype and our lifestyle that can then generate a real pain. Mainly among night owl / late risers have to get up early the week, and are catching up sleep debt weekend. They then experience a true “jet social lag” associated with a procession, metabolic, cardiovascular, cognitive (memory, cognitive disability), mental (endogenous depression, anxiety) …
France in debt chronic sleep
The situation is not going to be accommodating. Our lifestyles bully, in fact, increasingly, our biological clock and opposes our chronotype, prompting us to lie increasingly later with a poor sleep.
its annual survey, the National Institute of sleep and alertness (INSV) shows that the French population has chronic sleep debt. On average the French sleep 7 h 05 week and 8 h 11 the weekend, proof that they do not get enough sleep on workdays and thus do not sufficiently respect their rhythm. 73% of them say they wake up at least once a night. 25% are sleepy day. And third states suffer from a sleep disorder.
As much time in bed and with a screen has an impact on the quality of sleep
INSV points to the impact of new technologies that have “ very widely invaded day … as the nights “ and highlight the difficulty. According to the survey, 8 out of 10 French use their computer, tablet or smartphone in the evening after dinner and almost 4 out of 10 in bed “As much time in bed and in front of a screen has an impact on sleep quality” says Dr Joëlle Adrien President INSV. Users of new technologies in the evening put, according to the study, more time to turn off the light (from 9 to 12 minutes), to fall asleep (3 minutes), and 49% of those with a computer or in sleep in their rooms complaining of sleep disturbances. Involved, a double effect. Our connected devices, challenging and addictive, keep us in a sleep state, “on the alert”, turning us into “sentinel sleeper”.
But even more powerful, the direct impact of the light screens on our brain’s internal clock. “The light to which we are exposed in the evening and early night has the effect of delaying the clock” says Claude Gonfrier. called LED screens (TVs, smartphones, tablets, computers) cast a bluish light “extremely effective” .
Not surprisingly, according INSV, if exposure to screens recurs every night, nights of lesser quality and sleepy tomorrow are renewed. And little by little, sleep disorders are installed. “There is no question of banning connections, concludes INSV, just log out at the right time, minimizing of the possibilities being disturbed at night, rest days and holiday “
the recommendations of INSV better sleep
. – do not expose yourself to the screens in his bed
– Allow new technologies at least 1 hour 30 minutes before bed.
-. Banish laptops and smartphones of the room and put in airplane mode
– Disconnect the weekends and days off.
– Adopt a “digital courtesy.” Will impose time limits or day to connect with others
– Minimize screen brightness
. > – Using applications that reduce the percentage of blue light from a certain time.
-. Wear protective glasses
– S expose to the light of day that resynchronize the biological clock.
-. physical activity day