As I write this (with apologies to Robert Frost), the empty space on my couch looks sweet, but I have promises to keep, and six months and hundreds of miles to go before I sleep.

Training continues. I’ve always loved people-watching, and observing my fellow runners proves inspiring every time. Many have their own rhythmic "mad mantras" (e.g. "I hate this hill, oh DAMN this HILL"—lather, rinse and repeat), which seem to carry them through the peaks and valleys of each run.

Many run in serene silence from beginning to end. Still others manage to power through a two-hour workout chattering the whole way. (These are the same people who actually jog a couple of miles to warm up for a 10-mile run, who give each other sprightly high-fives at the endpoint, still as full of beans as they were when they set out.)

I don’t converse much during my runs; instead, I pull out a mental laundry list of things to think about, things to take my mind off the pain and the pavement. This week the question "Why?" topped the mental laundry list.

Most people, when they learned Scott and I were preparing for a marathon, said something like, "Wow, that’s awesome!" We basked in their kudos, propelled during our runs by others’ encouragement. Only last week did I have to answer the tough question: "Why do you want to run a marathon?"

I went for my standard response, which is profoundly true albeit slightly tired: "I want to do something amazing."

"A marathon certainly is amazing. So are lots of other things, though. Why’d you pick that?"

Indeed.

SO MANY THINGS about running are not enjoyable: the heat, the cracks in the sidewalk that can send you flying into an unforgiving bramble of thorny branches, the fact that I could be curled up in bed with my cats and a fantastic book but instead am outside in the sun (or rain). At least there is no sleet or hail to contend with, although when running in driving rain that seems to pierce the skin and makes it nearly impossible to keep your eyes open, this is hardly consolation. In the short course of our training, we have dealt with side, knee, back and foot pains. On days when we’re at our worst, we have become total pains in each other’s … necks.

And still, we run.

We are encouraged by our support team of family members, friends and co-workers to remember why we started. As 1952 Olympic marathon gold medalist Emil Zatopek put it, "If you want to win something, run 100 meters. If you want to experience something, run a marathon." We are chasing an experience that some would file just under waterboarding in "Effective Methods of Torture," yet we are searching for ways to make it unforgettably good.

As we reach for this goal, there are so many things we must bypass: the temptation to quit, the urge to eat that second cheesecake, the suspicion that running 26.2 miles is physically impossible (and that we are the unwitting objects of some grand practical joke) and, the most dangerous pitfall of all, the notion that this is an unnecessary undertaking.

Gen. George Patton said after the 1912 Olympic marathon: "If you are going to win any battle, you have to do one thing. You have to make the mind run the body. Never let the body tell the mind what to do. … (T)he body is never tired if the mind is not tired."

But back to people-watching: Of all the runners I’ve observed while training, my favorite to watch is Scott. His stride is one of total determination, and his face is totally focused … until he catches me watching him. Then he throws his arms in the air and does a couple of "grand jettes" down the pavement, sometimes throwing in a random show tune for good measure, always making me laugh and reminding me of one of the best reasons of all that we’re doing this. The next time I’m asked "Why?" I’m going to answer, "Because it’s fun."