He does not say nap, but "little restorative sum".

Damien Davenne *, a chronobiologist, teacher-researcher at the University of Caen and a sleep specialist, has worked with professional navigators to help them manage their short sleep phases during single-handed offshore races, such as the Vendée Globe.

In four key points, the researcher explains the secrets of a successful and truly restful nap.

Learn the art of "siester"

The nap principle is simple, but for it to be really effective in terms of recovery, you have to practice practicing it. Once you have the ability to fall asleep in just a few minutes, it's like cycling: it's not forgotten.

According to Damien Davenne, who each year transmits the art of napping to his Norman students, it takes 5 to 10 days to acquire the mastery of "nap" for life : "The ideal is to have a certain regularity in his nap practice, to accustom his central clock to a break in the early afternoon. The human being is naturally programmed to rest at midday, around 13 hours, and not later than 16 hours. Still, it is necessary to know how to listen to each other ".

According to the teacher-researcher, this "loss of vigilance" that we feel after the lunch has nothing to do with digestion: if we want to sleep up the canteen, this is not not because we picked up French fries.

"Homo Sapiens had a vital need to rest at midday because his nights were short, and his energy expenses very important. It is necessary to take advantage of this hollow of vigilance to take an effective nap ", summarizes Damien Davenne.

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15 to 20 minutes: the duration of a perfect nap

Whenever we try to take a nap, we wake up even more tired, the slow-motion brain caught in a particularly unpleasant cottony sensation? It's because we slept too long.

For Damien Davenne, a perfect nap should not last more than 15 to 20 minutes : "At first, you will probably need to put an alarm not to sleep too long. But with the habit, and if you stall your nap every day at the same time, you will end up waking up automatically, after 20 minutes. "

For the nap to be effective, it is also necessary to take care of the waking phase: do not straighten up, but keep 2 to 3 minutes to unfold the same sequence - to stretch, to move your muscles, to say that we feel better and in good shape, and only then, to recover.

"These tips are also valid in the morning, says the researcher. It should always go through a sitting phase, before getting up from bed, to allow the brain to be properly irrigated.

The image-doudou, the secret to trigger falling asleep

To succeed in napping on demand, you must have conditioned beforehand, with an element that will trigger the process of falling asleep , explains Damien Davenne: "For this we must choose a pleasant image, well known: a photo of vacation, or a poster in his office, whatever.

Only condition: that this image pleases us, and that it serves only to trigger the sleep. Then spend 4 to 5 minutes to examine in detail, starting from the center to the periphery of the image, spiral. The objective is to know it by heart so you can then invoke it mentally, without having it in front of you ".

Once we have it, we start by thinking about this image, mentally detailing it, from the center to the edges, whenever we want to take a nap.

In addition, to get rid of parasitic thoughts and achieve what Damien Davenne calls "a modified state of consciousness", the researcher recommends a well-known method sophrology: focus on his breathing . Become aware of the weight of your body, from head to foot, stopping on each part of the body. And so in a few minutes, with training, we should be able to fall asleep at the request. Yes Yes.

In the office, we take a nap in a sitting position

A final obstacle to the art of daily napping is the lack of resting space in offices. Difficult to lie on the carpet of the open space under the pretext of recovering from his morning ...

" It is possible to train to sleep in the sitting position , ensures the researcher, the office or transport. The recommended position is that of the coachman: the feet are well placed on the ground, the head between the arms folded on the desk. It is obviously necessary to prevent one's colleagues, and to learn to let oneself be traversed by the ambient noises without disturbing them. But as usual, these familiar noises will eventually slip on you. "

A detachment useful to improve its concentration

A detachment work which Damien Davenne assures is also very useful to improve his concentration at work .

A last tip of the professor: "It cools quickly enough when you fall asleep, it may be useful to cover your shoulders for better rest".

You are convinced? It only remains for you to find the pretty shawl or the soft stole that will accompany your small daily sums!

* Thanks to Damien Davenne, chronobiologist, research professor at the University of Caen, director of the joint research unit INSERM / Unicaen COMETE (Mobilities: Attention, Orientation and Chronobiology).