The Human Circadian Clock
Rupert: We picked up this earlier post from Peter Lewis:
"How long does it take you to recover from the "daylight saving" time shift? I keep waking up an hour early for over a week. It is a form of jet-lag without the carbon footprint. I plan to keep a log this year to see when I surface from sleep. Under stable conditions I will wake up at most half an hour before the alarm goes off. Most often the time is less than 15 minutes before. Sunday does not count, start on Monday."
More here too. A chance to find out more about your chronotype, are you a morning person or a night owl?