Why do we almost always fall asleep at the same time? Are we more creative at the end of the day? Do you remember your lessons better in the morning? Or:do you feel fitter at certain time slots? Chronobiology, the science that studies the body's natural rhythms, helps us determine the best time for a particular activity.
The functioning of each organ, and even each cell of the human body, is governed by an internal clock. All are synchronized by the biological clock located at the heart of the brain, in the hypothalamus. Like an orchestra conductor, she sets the tempo so that all the clocks are on the same rhythm. Thus, the metabolic, digestive, renal, respiratory, endocrine, nervous functions, in short the functioning of the body as a whole is regulated by this central clock, set on a cycle of approximately 24 hours, i.e. a rotation of the Earth on itself. .
The proper adjustment of rhythms - called circadians - determine mood, sleep, alertness, eating behavior and, more generally, physical and cognitive performance. Conversely, a desynchronization of rhythms can lead to health problems.
Chronobiology has made it possible to better understand these mechanisms. This science was honored in 2017, with the awarding of the Nobel Prize in Medicine to three American researchers, Jeffrey C. Hall, Michael Rosbash and Michael W. Young, for their discovery of the genes involved in the functioning of the circadian rhythm. They showed, in particular, the key role played by sunlight, and particularly by the alternation of light and darkness in synchronizing the biological clock.
Daylight is essential to the conductor, as it provides him with the information he needs to set the tempo. But to have a good day, you still need to have had a good night, because the quality of your sleep will depend on your mood and your energy. For this, certain rules must be respected:
To sleep well at night and feel fit during the day, good "light hygiene" is therefore necessary. If light is one of the most essential factors for the biological clock, the regularity and balance of food intake are also very important. Sticking to regular schedules, both for meals and for the various activities of the day, is essential to “tell the time” to your internal clock. Once these basic principles have been laid down, all you have to do is respect the natural rhythms of your body. This will help you choose the most suitable time to indulge in your activities.
At night, as we have seen, the released melatonin helps to plunge into deep sleep. Then, between 6 a.m. and 8 a.m., cortisol takes over. This hormone secreted by the adrenal glands plays a major role in balancing blood sugar levels. It helps to provide the energy needed during exercise by releasing the glucose stored in the body. The morning, just after breakfast, is therefore a good time for physical activity.
Mid-morning is ideal for intellectual efforts. It is indeed between 11 a.m. and noon that one is at his best in terms of memory and concentration.
Meal time has come. Take the time to take a real lunch break. You will gain in efficiency later. Around 2 p.m., the insulin level is at its highest. This is the reason why a small drop in speed, even a desire to sleep, can be felt. Then give yourself a short nap (twenty minutes maximum) to recover energy and concentration. The secretion of insulin, an essential hormone for the assimilation of glucose in the blood, is very sensitive to the biological clock. Anarchic meal schedules can disrupt its production and promote obesity or diabetes.
Between 3:00 p.m. and 7:00 p.m., you are in top form:you can work your brain as well as make physical efforts.
