Cecilia offered such a comprehensive post--you rock, Cecilia!--that I don't have much to add on the reasoned, rational response to your concerns. But here's a couple of things:
1) Weight Loss & the Lean Meaners. Word. We're there for accountability and the challenge. You have the time to lose the weight, Beth is a great example of doing races and steadily losing weight, and I'll be more than happy to match you glass for glass with the water. (Again, great info, Cecelia.)
2) Hell pain.


I agree with the shoes, agree with the stretching regularly. My cross-training focuses on flexibility as well as strength. Makes a big difference. Shoes, too.
3) Yes, a plan. My plan, although still in development, actually uses a longer training period and less time on the pavement than some others. Now's the time to experiment a bit with your pavement/XT mix, see what helps with the pain. I tend to use more elliptical now, when I'm trying to lose weight. Less impact, better for my knees.
4) The mental thing. Oh my gosh, that's the hardest part of the whole thing. Your post is par for the course, btw, and just the kind of feelings I've had (and will have again). Bingham's MfM is a good book for this, because it reminds you how much of a mental challenge this all is. There were times, again like Cecilia, where I was not my finest self. I was mitchy (a combo of mean plus, well, you know

), morose, and scared out of my mind. But there were also times that I felt so impressed with what I'd accomplished that I thought I could rule the world.

I pushed myself beyond what I thought I was capable of, and so will you.
Oh, and for the selfish moment, the one where I'll pretend to kick you in the butt? I so want to be there to celebrate with you after you finish!!
