The one I worry about is the silent stealth dog, you know the type, cycling down the road in your zone, kind of aware of a slight noise and the monster is all energy, no noise, intent on getting incisors into your thigh. Those I sprint for. The other noisy fellas are just doing what dogs do, barking and running. For that type I just continue at the pace I am going and talk to them like I would my own dog.