So, I've been doing a lot of really long industrial narration sessions lately. This means pages and pages of technical, verbose writing and lots of talking, talking, talking. I've noticed that with these sessions, since I have elected to sit down to maintain a consistent level of energy throughout, I've gotten really yawn-y. Now at first I assumed that I was yawning cause I'm sitting in a dark-ish booth, droning on and on about a fairly dry subject, and maybe haven't gotten as much sleep the night before as I might have liked. So I started getting curious, and experimenting with switching the time of day the sessions were scheduled. I would do them first thing in the morning, in the middle of the day and even late in the afternoon, all with the same result. About 30 pages in, and I just start yawning away.
Then I realized, you don't just yawn when you're sleepy, yawning is a natural reflex when you aren't getting enough oxygen. Voila! I've started to focus on deeper sustaining breaths and the problem has drastically reduced. I mean after an hour and a half, 100 pages into a long narration, you're bound to have your brain a little muddled, but maintaining strong diaphramatic breathing has made all the difference. Corporate dialogue here I come!