O.K. I rode 15 miles with a lot of hills and a strong head wind. I know this isn't very far for some of you on here. But here is my question when I got done I put on my running shoes and tried to run I ran a few hundred feet and got a cramp in my calf. I walked for a little and tried running again it cramped. Is this from dehydration or my muscles aren't conditioned for this yet? In 2 weeks I got a Duathlon I'd like to do it is run 3.1 miles bike 18 and run 3.1. It is a mostly flat course Do you think if I pace myself better my calf won't cramp again?