Thanks for all the info, I will check out those books soon. I was also trying to find out the best way to stay in shape over the winter ( I need to drop ~15 pounds still...) and never thought of Yoga.
My DZ does have a deal with the Tunnel in NH, but I have a friend who was been jumping for a long time has a in at the WT in Boston as well. I planned to hit one or both of them a few times over the winter.