When I was last at my doctor, we were discussing sleep, and getting, or not getting, enough. What is enough? Enough for me, is an amount that allows me to awaken naturally, rather than being blasted out of sleep with the alarm. When the alarm wakens me, I feel instant resistance, I don't want to get up. Even if I've set it the night before so that I may meet my obligations, and even as I'm getting out of bed, I'm thinking to myself that I hate getting up early.
It's all to do with feeling forced. When I awaken naturally, I feel as though I've had enough sleep. When the alarm pushes its way into my brain and brings me forcibly to the surface, to wakefulness, my entire system revolts. I try to get up at the same time every day to keep some structure in my life, but that requires retiring to bed the night before, sufficiently early that I will sleep long enough to do so.
When my normal system is interrupted, it's always because I'm struggling with something which interferes with my serenity to such a point that I cannot go to sleep.
My body is always the first sentinel warning me of lapses in my serenity. I get vague headaches, and my eating habits slide, and all because of my mental state. When I ignore these changes in my usual habits, I ignore myself.
My body is the temple of my spirit, and as such, it deserves respect.