Originally Posted by Kyle Clayton
Why does the body care what time you go to bed as long as you sleep enough?
I usually get to bed between 10 and 12 due to work and school, and I'm a light sleeper so it takes me a little while to get to sleep. I'll wake up at 10am having slept for about 9 hours.
Because your body's internal hormonal clock is not dictated by tv guide and artificial lighting, but rather by a bigger force in nature (circadian rhythm...for more info on that I would suggest reading "Light Out:Sleep, Sugar and Survival"). That's in an ideal world....but most people go to sleep later anyways (like myself). Your best peak of GH while sleeping is between 10pm-12am....if you go to bed at 12pm then your GH peak is a fraction of what it should be. Hence why people who go to sleep early may sleep less...and people who go to sleep later may sleep longer and still feel tired waking up.