Decisions, decisions...

I need to decide in four days whether or not I am going to run/walk the half-marathon. February 1 is the starting training date. If I don't start by that date, then the jig is up. I won't survive. Part of me really wants to commit, and the other part is saying NOOOOO! I got approval from my asthma doctor (hurdle #1). He thinks I am doing great! My DH (hurdle #2) is now thinking he doesn't want to do it. He would rather have us go skydiving. I am afraid of heights, let me rephrase - deathly afraid of heights. I don't think I could do it! I tend to like the safe things in life - GROUND! He also suggested bungi jumping. I wonder if this is the start of a midlife crisis for him...