I came across this idea about how to structure your day. It was related by Karen Wright on the Great Work Interview podcast, and attributed to Marcia Conner. It’s about how you get the best use from your energy level at different times of the day.
Use your head for thinking, when your energy is naturally greatest (for me that’s morning).
Get up and do something active when your energy flags (for me, after lunch).
Sit quietly and reflect (for me in the evening).
I’ve still to think through the practical application to a normal working day. But I like the theory!