Originally Posted by valpal215
tell us more about this 90 minute sleep cycle of which you speak. I haven't heard of this before, but I sure have trouble getting up at 5 am because I'm always in the middle of a great dream . . .
Hmm I guess what I mean to say was "deep NREM sleep", meaning you are in deep sleep and it is harder to be woken up, if your alarm goes off you will probably just fall back asleep if you don't get out of bed right away. The cycles are different for everyone, but once you are aware of what they are, you can recognize them and adjust your sleep schedule accordingly.
Do a google search on "rem sleep" and you'll find more information, this link contains a chart to explain it more visually: Getting the Sleep You Need: Sleep Stages, Sleep Tips and Aids
But to be honest I am no expert on the subject.