If you have your hands up you will get less of a workout because your running slower you may even give up quicker, also the arm action is important if your doing sprints.

If you want to improve your ring work you can focus on footwork on the heavy bags, in sparring. Or get in the ring with friend and spar but dont land any blows just practice evading them and your game plan, then swap roles and now your cutting the ring down and getting them up against the ropes. You can also get in your boxing stance and practice you footwork using your imagination of fighting an opponent, this better than a running slowly as your using technique and an action you would preform in the ring,(no boxers run in a fight they dance) eg front foot stays forward, body turned so less of a target, on toes, widen your stance when you move so going left is left foot then right but is done so fast it is one fluid motion.

I use running as a means to improve endurance/heart LSD long slow distance, or to improve anaerobic endurance short distance and fast