I am doing IMCDA on June 21, 2009. I've already planned on a half-IM on April 18th as a tune up race and just to see where I'm at. Would you suggest doing a marathon or would the recovery take away from any possible benefits? I don't need the mental edge because I've done more than my share of marathons, but I do want to do everything I can to make my IM the best ever. Thanks!
I would actually put much more weight on your half-IM, and skip the marathon.
The reason to do to the half is that it is a great little "dress rehearsal" for a lot of the clothing, equipment, and fueling decisions that you'll be looking to make about CdA. Nothing like a higher intensity race like a half to give you an idea of what it will be like to wear/use/eat/drink whatever...you'll come out of there with lots of good ideas, I'm sure, so take notes!
"Straight" marathons are just plain hard, period. Yes, tri folks can scoff at the thought of "only" doing a marathon, but I tell runners all the time that the four marathons I've done have all been harder than my hardest marathon at the end of an Ironman (18 and counting ;-)...If your IM race was in Oct/Nov, you might look for a marathon in July as a way to focus your training, but since it's early -- and especially because you say that you don't need the edge -- I'd skip it completely, no doubt.
I agree, I have grown to loathe plain old road marathons (although I keep signing up for them). I am actually very happy you confirmed what I was thinking and hoping:) Since we're on the topic, how hard should I race the half, I'm guessing all-out would be tempting but silly. Probably go IM pace, maybe a tad faster?
Oh c'mon, go as fast as you can, always! That's why they call it a "race"! ;-)
Seriously, you'll be conditioning your body to take the race seriously, you'll get a better practice "dress rehearsal", and you'll come out with a more positive experience if you focus on it hard and go for it. Don't be afraid to be an athlete -- plenty of time to recover afterward!