Running

If I were interested in a form of a self defense weapon that I could easily take with me while I am running what would be the best one? I have been trying to research something that would be instantly effective and that I do not have to have a lot of skill to operate. My goal is not be skilled in self defense but I want a tool that I can instantly scare away an attacker should one get a little too close for my comfort. Would taser guns be a safe weapon of choice for all my requisites in protection?