Weight Training and Pregnancy??

So, in preperation to conceive (we're hoping to sometime soon) I've stumbled on the age old adage regarding working out and the inability to conceive. My family swears by it. I'm not sure what to believe. I've heard of marathon runners that conceived while prepping for their big run. So why should I be so concerned about this? My husband and I have been trying for 9 months with very little luck. I'm just going to continue my workouts and maybe scale back on the runs a bit. It just saddens me that I am still so confused about this kind of stuff...I know you have to have an optimal amount of bodyfat to conceieve (which I do!) but am I making myself barren?

I need to look into this further....

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Update: To any pregnant mommies out there, I've just stumbled onto a page that was super helpful. check it out...http://www.bodybuilding.com/fun/pregnancy.htm

also...

http://www.bodybuilding.com/fun/simone3.htm

lastly...I picked up this bad boy yesterday. I was so excited to get it at the very good price of "FREE" that I felt like running around the neighborhood with my dog in it. Ok..probably not a good idea since he's a full size Boxer :)