I thought I'd never become a runner until I joined a fitness bootcamp. Not only was I proud to be able to run five miles without getting winded; I loved the overall feeling of well-being. Now that I'm on my own (temporarily) I'm hearing one should not run outdoors on cement. However, at bootcamp they claimed it was good for women's bones??? Anyone here have any insight on this? I want to continue running/trotting outdoors but don't want to mess up my knees.