Triathlon!

I've recently given my X-Bike class (5:45am!!!) a challenge--to do 24 fitness activities in the month of February, as well as one fitness activity that is way out of character and out of the comfort zone.
As an instructor, I can lead by teaching a class, but I also need to lead by example, so this afternoon my husband and I took a very wiiiiiiiiiiindy walk together. We worked a little harder than usual, pushing through the wind, which was kind of fun. My hair looks like a bird's nest, but my bones and heart are happy!
For me, my own personal "outside the comfort zone" activity is going to be a sprint triathlon, especially set up within the Y where I teach X-Bike (pool swim, stationary bike ride, treadmill run). I've never done a triathlon, but know so many people who have, people who are normal and not uber-fit. My big achilles heel is my foo (not my achilles heel, though!), so the running is an issue. The swimming I've licked--for the past six months I've been swimming laps and actually have a three-stroke rhythm that seems to work pretty well. The biking, no problems there. But doing all three together? It'll definitely be a challenge. But the worst that can happen is that I'm miserable and sore the next day, and I like the soreness from exercise, and this will hopefully break yet another barrier I've built for myself, the wall between me and the triathlon.
Do we, the formerly awkward last-to-be-picked-for-the-team kids ever get over that image of ourselves as non-athletes? I keep wondering as I enter my 20th year of fitness instruction. I guess growing up doesn't stop until we stop caring.
I really never want to grow up.