Seasonality in freerunning circadian rhythms in man.
Retrospective analysis of data collected over 15 years in normal subjects isolated from time cures showed seasonal rhythms in the circadian period of the core temperature rhythm, in the amount of sleep (both shorter in spring and longer in autumn), and in the incidence of internal desynchronisation (most often in summer). Women slept longer than men at all times of year.
D001831:Body Temperature; D002940:Circadian Rhythm; D005260:Female; D006801:Humans; D008297:Male; D010507:Periodicity; D012621:Seasons; D012890:Sleep / Q000502:physiology