Nope, there was not. There were mods I think for the PC version (sprinting used up your AP), but nothing in the game by default.
As said, this is an RPG, not an FPS like Halo, CoD, or Battlefield. Your character runs as fast as their body allows them to.
Who needs mods to run? You just run :shrug:
Basically holding SHIFT causes your PC to do the opposite of what your default is set to... If you walk by default, holding SHIFT will make you run, (and Vice Versa if you toggle the Capslock Key).
The PC cannot run if overloaded, in this case you just drop some of the weight, and then they can run again.
On the XBOX... I dunno exactly how... but its a fair bet that it must be in the manual somewhere... and if not :shrug: Does the Xbox allow configuring the game controller?
My [utter] guess would be that there is a button that you hold while moving that might cause you to run.