Rather than commenting on Undine's post, I'll do my own one. I am having a zombified day. I slept badly and feel very thoroughly brain-dead. I tried doing some class plans (on the theory that if I plan the semester when I feel like this, I won't give too many assignments to grade), but that didn't go too well.
I wish I could work well at night. Every now and then, especially after a zombie-day, I'll have a burst of useful energy in the evening. Mostly, though, if I don't write in the morning, it doesn't happen. My ideal schedule is the one I followed Monday and Tuesday this week, before the sleeping problems kicked in: up by 6, put in an hour and a half in my study, then do yoga before getting dressed and arranging breakfast for both me and the cats. After that I can go on to be productive in other ways, or to write more. But it does depend on going to bed early and sleeping well.
The big problem is that I can't arrange my whole life to allow me to go to bed by 10:00. Most of the LRU English Department's graduate classes, and some of its undergraduate classes, are taught at night. Sometimes I get lucky and get an afternoon grad class, but in most semesters I have at least one night a week where I'm on campus till what seems to me like a late hour, and then I still have to drive the hour home. Teaching leaves me wired as well as tired, so once I am home I can't go straight to bed; I need to wind down for a bit. Then if I want to experience Culchah, such as the Theatah or the Dahnse, or just go out with friends or engage in some organized activity, there's another night or several when I'm not going to bed in time to get up early.
So I've tried various tricks to make it possible to get writing done, such as my writing dates with a friend, which usually take place in the afternoon. Or I'll go to the library between classes (if there is a between-classes slot, which this fall there will not be). One of my old friends swears by doing all teaching prep on teaching days, and having the other days to do research; but this does not work if, due to a long commute, one's on-campus days are full of committee meetings, crucial library time (even just checking out and dropping off is not a zero-time activity), office hours and essential on-campus errands.
I envy night owls. I bet they think the world is set up for people like me, but I think a lot of things work better for them.