1. Picked up the horn and warmed up using my usual routine.My chops lasted much longer doing this, and feel better afterwards, than if I just play for an hour straight -- and I probably got just as much accomplished, if not more. This reminds me a little of a typical rehearsal in any band -- you play for a few minutes, then you listen to the conductor tell you something, then you play for a little bit longer, then you sit there while the clarinets are being worked with, then you play again...
2. Walked over to my computer and answered an e-mail.
3. Picked my horn back up and did some flexibility exercises.
4. Checked on my applesauce which was cooking away in the kitchen.
5. Played some high range exercises.
6. My cat demanded to be played with, so I made her chase her feather toy for a few minutes.
7. I played through the second movement of the Kelly Sonata.
8. Potty break.
9. Worked through some tempo issues in the Kelly piece.
10. Answered a phone call.
11. Played through the whole second movement again, much better this time.
12. Put the horn down.
I have always heard that taking frequent breaks during practice can help the practice session be more productive. Joe Jackson writes that practicing in short, varied sessions is one of the seven habits of highly effective trombonists. It's difficult to do this when your only venue for practice is a practice room somewhere, but I have taken to leaving my horn out on its stand in the dining room to encourage myself (and anyone who happens to drop by) to pick it up randomly and play something. So far, it's made a big difference -- maybe I'm finally learning how to practice.