Stepping Out the Door

The hardest part is getting out the door. But that's the commitment part; the part that tests me. I did not want to go for a run tonight. I wanted to stay in and do...anything. But I know from experience that once I've laced on my shoes and I've stepped out the door the rest will take care of itself, and that when I'm back home I will feel better than I have all day. And so I went. And now I do. Why is what's good for us often so difficult to embrace?