It’s a Beautiful Day. Let’s Run 26.2.

I guess you don’t really know what you can do unless you try.

Jen and I had been training this summer for what would be our third Chicago Marathon when I developed some bad knee pain in early August. I figured I’d take a week or so off and it would get better and my training would go on. Well, one week led to two and then three and it was apparent that I wasn’t getting better.

Went to see the orthopedic surgeon who said “you’ve got Runner’s Knee. Do some PT and stay off it for a while.” So, I mentally put Chicago out of my mind, fought off a mild case of runner’s depression and began cross-training like a maniac with swimming and cycling. Hell hath no fury like a runner denied. . .

Well, about two weeks ago, after six weeks of no running at all, I gingerly went for a ½ mile run and had no pain. Two days later, I did 1 mile. A few days after that, two miles. Still, I was harboring absolutely NO illusions about running the marathon this year and was already thinking about next year. And, I was getting excited for Jen and helping her focus on her goal of going sub-4:30.

As the days counted down, we decided that on the day of the race I’d take the Red Line down to Chinatown and jump on the course with her with about four miles to go and run with her for the final stretch. Seemed like a plan.

Jen and I headed into Chicago on Friday for the Fitness Expo at McCormick Place where you pick up your packet and experience the dozens of very cool running-related booths with all kinds of stores and vendors selling everything running. It’s like a crack house for runners.

Well, being surrounded by all that running mojo forced me to change my tune. Why don’t I just start the race with Jen and see how far I can go? They have runner drop out shuttles at every aid station to take people back to Grant Park. They’ll be no shame if I can only do a few miles and then call it a day. Seemed like a new plan.

The day dawned cooler than the 2007 humidity-laden trainwreck of the Chicago Marathon. However, the forecast was still calling for sun and temps in the high 70s to low 80s. We started the race and I felt great. We clicked off the first couple of miles at 10-minute pace, right on Jen’s target to break 4:30.

Chicago’s course plays a cruel trick on runners in that the first four or five miles take place inside the skyscraper canyons of LaSalle and State Streets. These are very narrow streets where the roars of the spectators give you a palpable chill down your spine. It’s also very shaded, thanks to those buildings, and it’s hard to remember, at that point, that the sun will soon become a factor.

Right before mile 4, I jumped off the course near an aid station to use the Port-O-Potty and told her to keep on going. That was the last I saw of her. She would finish in 4:28, beating her 4:30 goal by two minutes. She’s a machine.

No big deal. I just kept running and was clicking off 10-minute miles. Five miles passed, then six, then seven. We had been out on Cannon Drive, now in the sun, for a while and I was still feeling really good.

At one point, I thought, “wouldn’t this be a great story? Hardly any running for about 8 weeks and then I finished it anyway.” Then, reality set in and I realized that I still had about 19 miles to go.

Suffering for runners is exponential. If you’re feeling good at mile six, it’s entirely conceivable that you can feel crappy at mile seven, thanks to the cumulative effect of those first six miles. So, I told myself, “just take it one mile at a time and see what happens.”

So, I passed through Broadway and Clark and then continued the journey south on Wells for two miles. Still felt good. No knee pain, heart rate dialed in well and 10- minute mile pace holding steady.

Mile 12 is one of my favorite parts of the course. You turn right and pass under the El tracks and then make a quick left on to the Franklin Street bridge over the river. There’s a ton of people on the corner and it helps you get your tired legs over the bridge.

I crossed the 13.1 mile mark at 2:15, still right around 10-minute pace. Though I was stunned to have even made it this far, things began to get a little more difficult around the 14-mile mark. A blister had been developing on one of my toes and I stopped very quickly at the aid tent, put a Band-Aid on it and went on my way, feeling much better. At this point, I began to have a few more little thoughts about actually finishing.

Two miles on Adams heading west toward mile 15 was a little tougher. The fatigue was setting in a bit, I was down to my last PowerGel and the heat was climbing.

I think miles 15 to 20 are the most difficult in a marathon. You hit 15 and you feel like you’ve accomplished something, until you do the math and realize you have 11 to go. This time was no different. We turned back east on Jackson and I took my last PowerGel for a little boost, hoping it would get me to mile 18, where the PowerGel Zone would have more gel packets.

I grabbed four gels right before mile 18 and kept digging. I took a gel immediately, walked a bit, got some water and was feeling better. That didn’t last. The lack of miles in my legs from not running was catching up to me at this point and my quads were feeling heavy. I kept picking out landmarks, would run to them, stop a bit, and then keep going.

Mile 20 was a relief, to be honest, and I was even surprised to see my time at that point. Finishing was now a viable option and I even began to see a way to break five hours, which was not bad, all things considered.

Shuffled through miles 22 and 23, passing a fully-dressed Elvis in the process, who looked very hot in his polyester jumpsuit. “Just get to South Michigan Ave.,” I kept thinking, “and you’ll be in the homestretch.”

South Michigan Ave. came upon me quicker than I’d expected and that’s when it really dawned on me that I was going to finish. The corner of Michigan Ave. and Roosevelt Road is holy ground for those of us who have run Chicago. It’s packed with people and it’s when you really feel like you’re nearing the end of a long day. From Michigan, you make a right turn on to Roosevelt, and run up a very nasty hill, really the only significant one on the course, then you turn left at the crest and head down the last 200 meters to the finish.

I hit that corner and was just overcome with emotion. Not so much because of the physical effort but for the psychological surprise of pulling it off. I crossed the line in a daze, mouthing “Holy s***” over and over. Looked at my watch and smiled at the 4:53:08.

Two days later, my legs are shot. My biceps hurt. My toes are very tender. I’m sunburned. And, I’m feeling great.

What did it? Was it the man I saw around mile 13 running with an artificial leg? Was it the woman in a pink shirt with the words “20-year survivor” written in Sharpie who I passed around mile 14, causing me to think, “I have no excuse not to finish this.”

Was it my good friend, a cancer survivor, who’s faced the toughest test of all this year overcoming a terrible disease which makes most of our everyday struggles look pedestrian? Was it my sister, who faced some phenomenal challenges this summer and overcame them to bring a beautiful baby girl into the world?

It was all of that. I drew on all of those things for inspiration and crossed the line knowing I was being pushed by something beyond me. I’m under no illusions that running a marathon is the hardest thing to do in the world. It’s not.

What I do know is that many of us seek challenges that make us suffer physically and mentally, that make us really reach down into the depths of our souls and ask ourselves “how bad do I want this?” How much can I take? And, we do it because it makes facing other challenges that much easier.

Most marathoners will echo that thought. “If I can run a marathon,” we think, “I can do anything.”

The suffering is addicting. The accomplishment is lasting.

And, oh yeah, it’s only 362 days until the 2009 Chicago Marathon. . .