Like TPease68, I just run right behind them, don't get too close or you'll be pulled into a battle easily. I'm not sure if it's just me but sometimes they stop running for just one or three seconds but they move their legs even when there not running, when they do this, try to notice it quickly, when they start running again just go ahead and keep following.
Like the others said, run behind them carefully. And at the end of a battle with them, sometimes the easiest way for me to get away from them is to "click on the Commons" mark to leave the area quickly so I don't get pulled back into a fight again. It means I have to walk (or fly back to the area), but at least I don't have to battle them again! Bailey Mythfinder