[skunkworks]

You can't train for a marathon without hurting that training. Trust me, I've done both. Running long distances beats up your body and depletes energy stores, which gives you less explosiveness and performance when you hit the weights and forces you to take more time to recover. I think it really affects it most in the recovery, not to mention the fact that marathons require slow-twitch muscles and you're looking to improve the fast-twitch stuff.