I've recently happened upon a way to increase your sprint speed to nearly double! Simply spamming the attack button with a dagger while sprinting allows your to travel even faster than usual If you have the elemental fury shout and/or duel flurry perks maxed out you can go even faster! I am on an xbox so this might not apply to other systems.

Everyone runs faster with a knife?

Confirmed. I just grabbed a knife from my kitchen and chased some kids down my road. My running speed has more than doubled!

Lol gotta love counter strike references