If your using the unlimited sprint feature, take it off.
That was the issue for me..
Yep that should solve it. Its even written in the trainer instructions!
"Numpad 6: Unlimited Sprint - toggle this on and then begin sprint.
Your sprint will remain full and you can run unlimited. You may
have to turn this off if your character has reached the destination you want but still wants to move, etc."
[Edited by iCruze, 5/4/2012 4:15:39 AM]