Running is a lot like writing. This is one of those statements I feel qualified to make because I'm currently occupied with both: I just started training for a half-marathon, and I'm currently in the middle of trying to make my NaNo soup look more like a linear story. Don't believe me? Read on.
1. They both operate on delayed gratification. Sure, you can go for a run tomorrow. But when will you start to see the results? If you're like me (motivated by the desire to be physically fit and less flabby), it's going to be a few weeks before the physical changes start kicking in. In the meantime, you have to bust your butt and take the pain.
It's the same thing with writing. Sure, there may be instances of "IAFOS! The perfect sentence!", but by and large writers are partly motivated by the desire to develop their skills, finish books, and ultimately get published. Again, these are not changes you are likely to see tomorrow. And probably not in the next few weeks, either. (This is an instance of running delivering before writing does.) But if you keep at it, your writing will improve. You will finish your first draft, and then your second. And if you have the discipline and patience to keep at it, you stand a shot at being published. (Eventually.) (And because the rest of your puny competition will have thrown in the towel.)
2. They're both occasionally painful. Ever felt the muscle seize up after you ran four miles for the first time in months? Yes, that's painful. I've been running for four weeks now and still occasionally wake up sore. Don't get me wrong, I actually kind of enjoy it. It makes me feel like I've accomplished something. But it's still pain, and it doesn't really make me thrilled to get up in the morning and get to the track.
Writing? Well, keeping to a schedule and writing every day is painful too, at times. Sometimes it's really hard. Sometimes all you can do is stare at the wall and think thoughts along the lines of: "I hate this story! This sucks! It's so unoriginal! Everyone's doing vampire/werewolf/zombie/mermaid/unicorn books these days! No one is going to like it! It's not the same as it was in my head!" I may eventually take back this statement, but for now I'll lay it out there: Writing is generally painful. Writing is generally hard. But if you want to be a writer...it kind of needs to get done.
3. They are both worth it. I was a serious athlete in high school, and continued (sort of) in college. But now that I have an office job, it's difficult to motivate myself to get moving after a day of mind-numbing paper-pushing. But I still do it (and hope to continue). Why? Because exercise is key to a healthy lifestyle. Because it helps me sleep better at night. And because (yes, it's vain) I want my body to be attractive (in a healthy way), and I don't like that it's only my own laziness that stands in my way.
I also want to be a writer. I want it so badly, sometimes I can't sleep because of it. I read the agency blogs, I know the news, and every time I hear about a new book deal I think about how that's going to be me someday. Every day I sit down to write and push through the can't-find-words syndrome, that's a day closer to being where I want to be, no matter how few or how silly my words are. It's an accomplishment, writing another 750 words, running another 4 miles. It's work towards my goals. And that makes it all worth it in the end.