Writing is to Running as...???

I inherited t-bone's copy of a book entitled "Writing Your Dissertation in Fifteen Minutes a Day" by Joan Bolker. I'm not far enough into to determine whether there's any actual useful advice (of course, t-bone has already completed her dissertation so maybe proof is in the pudding), but I was tickled by the analogy she makes to creating a writing addiction to running. Here's the exerpt:

For some of us, writing gives us a place to be with ourselves in which we can listen to what's on our minds, collect our thoughts and feelings, settle and center ourselves. For others of us it gives a chance to express what would be otherwise overwhelming feelings, to find a safe and bounded place to put them. For some, it's like exercise: this is the way we warm up a muscle that we are going to be called upon to use.
--snip--
The satisfaction of writing every day is very much like the satisfaction of a daily 3-mile run. One begins, lives through the warmup, hits stride, has the experience of "being run" rather than "running," of a fluidity of motion that one no longer has to direct and then, cooled down, can feel, "Now the rest of the day's my own. I've done what I most needed to do." And for those who've never run? Writing offers the pleasure of a deep, ongoing engagement in an activity that is meaningful, one where you know more at its end than you knew at its beginning.

I'm trying to get into my writing stride and it ain't easy. Like running, the beginning is the hardest part where the pain is most intense, but eventually you settle into a stride. In writing, ruminating over how to begin is the most painful, but once you get a few sentences down that actually start to make sense you do get into a writing stride. Fifteen, thirty minutes or an hour later you've got something down on paper and it really does feel like you've accomplished something. But, the stride just doesn't happen the first, second, or third time you try - you gotta work at it, unfortunately. Gotta work on my stride, girls. Gotta work on my stride.