Because I'm pregnant.
I apologize for my secrecy, seeing as how I've known for about 2 months now. But, if it makes you feel any better, I'm 12 weeks into my pregnancy! How's that for ironic?!! Each trimester is 12 weeks long! Things that last for 12 weeks is my life!
So it looks as though I won't run the half marathon, not because my doctor says I can't, but because I have been so tired I can hardly think straight. However, I'm on to my second set of 12 weeks (read: 2nd trimester), and now that I'm "out" with my news, I can blog about pregnancy workouts!