Betty, Timmy, George, Cal -- thanks for the welcome. Apparently I am very wordy, as the logs are sure ticking by quickly.
So today I experimented with running. Its been cold-ish here, but generally snow free and I've been trying to figure out my cardio in the "in-between" period where bicycle riding is quite nippy but there isn't snow on which to cross-country ski.
Many eons ago I tried and quickly abandoned running because I'd get a horrible stitch in my right side after a few minutes and it wouldn't go away. I spoke about this problem to a few runner friends, and the consensus was this situation is caused by inadequate breathing. Oh, and that I was a huge pussy and could just run through it.
Today is cold and sunny and I was going stir-crazy. So I put on my running shoes (some Saucony low-end model) and started out. I ran for 6 minutes before the horrible stitch started. I did not stop, walked for 2 minutes until I felt better, then ran for 4 minutes and walked for 1 min. Then after that I ran for 13 straight minutes back home, for a total of 26 minutes out my first time with only 3 minutes total walking. I dealt with the stitch by being sure to breathe deeply in though my nose and out through my mouth. That seemed to work.
I didn't love it, but I didn't utterly hate it either. I might even be willing to try this again, assuming nothing hurts me too badly tomorrow.