To lose weight? New Years Resolution? Love for it? You have to? It's a lifestyle? Maybe it's to eat that hamburger later?
Whatever the reason is, you go out and run. For me I love running long and it's a lifestyle for me. And so in my personal opinion that is a wholesome way to motivate myself to go and run. What I mean by this is that if you're struggling to push, to go out and perform, find something about it that is positive and long-lasting. In any sport you need a reason other than to lose weight or eat a hamburger later. Your reason needs to be meaningful and able to take you far.
I have a friend who says he hates running and working out in general, but he says it's a "necessary evil." This is not an enduring motivation or opinion. By this he holds himself back and cannot push hard enough and go long enough to reach his full potential.
So just remember to go far and push hard with a fulfilling motivation. Because that will be a lifestyle that betters you!
Why do you go? Tell me!