Sleep patterns, evaluated in hunter-gatherer populations, show that without artificial interference, sleep is of course concomitant with the decrease in luminosity, but is also regulated by the outside temperature. Light pollution from night lighting and artificially regulated temperature contribute to distancing us from these physiological signals. In addition, the leisure activities linked to the screens encourage a voluntary restriction of sleep manifested by a later bedtime, whereas social constraints always impose the time of getting up. Sleep debt accumulates during the week and compensates for non-working days inducing a social jet lag of small amplitude, but repeated each week. Subjects who spontaneously or habitually develop a late chronotype (i.e. a propensity to be a late sleeper, late riser) are the most exposed to this social jetlag between days worked when the sleep debt accumulates and days off when the sleep debt compensates.~It has been widely demonstrated that a short sleep duration promotes weight gain. Subjects with a late chronotype associate a short sleep duration on days when they work and a significant social jetlag on days when they do not work. This late chronotype is associated with unfavourable eating behaviour and more emotional eating and constitutes a risk of developing metabolic diseases.~Confinement disrupts social habits: lack of work activity or teleworking creates the possibility for individuals to work and/or sleep at times that are most convenient for them. Investigators hypothesize that subjects with a history of obesity will have tended, during confinement, to return to their spontaneous chronotype. The evolution of chronotypes between the pre-confinement period and during confinement will allow to measure the percentage of subjects who are not usually living according to their spontaneous chronotype, due to social constraints. Finally, we wish to retrospectively question the subjects on the impact of confinement on their eating habits, physical activity, mood and employment.
Confinement disrupts social habits, the absence of professional activity or teleworking creates the possibility for individuals to work and/or sleep at times that are most convenient for them. Investigators hypothesize that subjects with a history of obesity will tend, during confinement, to return to their spontaneous chronotype. The evolution of chronotypes between the pre-confinement period and during confinement will allow to measure the percentage of subjects who are not usually living according to their spontaneous chronotype, due to social constraints. Finally, we wish to retrospectively question the subjects on the impact of confinement on their eating habits, physical activity, mood, employment, and so on.