>Cross Training>Weight lifting and running
Your toughness is made up of equal parts persistence and experience. You don't so much outrun your opponents as outlast and outsmart them, and the toughest opponent of all is the one inside your head." - Joe Henderson
Depending on whom you listen to the advice is that weight lifting will add too much bulk to a runners body or that it is an essential ingredient for getting stronger and thus performing better.
And what do you do for abs/core strength?
Roads were made for journeys...
I really believe weight lifting is beneficial to running! Not only does it help my performance but it helps injury prevention. I've been lifting seriously for the past year and a half during which I have ran 1 marathon, several half marathons, 5k's and a 10 miler as well keeping a weekly milage of over 20 miles