I had my first brick workout about a month ago. I got off my bike after an hour, feeling fine, changed into running shoes/shorts, went out the door... and almost fell flat on my face. My darn stems just weren't working!

I talked to a friend who is a certified cycling/Ironman coach and after teasing me a bit, suggested this: After every bike ride (I ride every other day), schedule a very brief run. Not far or long, just a quarter-to-half a mile, enough to get my body used to the idea of transitioning. Once I get accustomed to it, the true brick workouts can start in earnest. Up until then, I can still get my regular running in on my off-bike days. I'm nowhere near ready to race, but I'm working on it.

Good luck in your race!
Joy