Tuesday, September 20, 2011

20

Physiologically, there is a certain point at which the human body has gone past its natural limits-- that is, when it has expended all its stored energy. According to runners old and new, there is a natural "wall" around mile 20 of the marathon. Despite the fact that a marathon is another 6.2 miles after that, most marathon training schedules never have you run past 20 miles. Scientifically speaking, the reason for this is that your your liver simply can't store any more glycogen than it takes to run that 20 miles. Even if you keep drinking gatorade or eating nutrition, your body will simply use it all up, and your body starts to break down after that point. The best analogy, as an experienced marathoner put it to me recently, is that the last six miles feels like running when you're completely hungover (which I have never attempted, but it sounds awful).

When I have explained this to some friends recently, several have asked the following: "Why don't you practice running past that point in the training schedule? Wouldn't it benefit you to see what it's like to run past that wall and keep going?"

According to several sources, running past 20 miles would actually hinder my training. Past that point, the body can't really recover fast enough for me to keep training right away, and I may even injure myself. After the marathon, I may be barely able to walk for several days, because I have simply pushed my body past its breaking point. 

This past weekend was my first-ever 20 mile run.  Flash had done a 20 mile training race called "The Revenge of the Penguins" (which is the nickname for slower endurance runners) as a training race for Marine Corps last year. Our training schedule doesn't necessarily call for the 20 milers to be a race, but the benefit of having aid stations as well as other racers to keep us company for three and a half hours is too large to pass up. Surprisingly, I didn't dread the race at all; possibly because I had handled the 17 mile run reasonably well. I even helped my friend move later that afternoon. Basically, I couldn't think too much about the enormity of the undertaking or I wouldn't be able to motivate myself to begin. Moreover, I knew that my fitness level now is such that I am capable of doing it, even if it's not particularly fast.

Saturday dawned with perfect weather for a really long run: high 50's to low 60s and cloudy, almost chilly.  I have gotten into a good routine recently of going to bed really early on Friday nights and waking up at the crack of dawn to go on long runs, so I felt pretty rested. I drove up to Calderock, Maryland on the Clara Barton Parkway for the start, which seemed like it was out in the middle of nowhere.  I knew that we would be running on the C & O trail,, but what I didn't know was that we would essentially be running from the forest up north down to where it begins in Georgetown and back up again. I ran into Flash and his friend Mer (a 7-time marathoner) before the start, but I still had to get my race bib and timing chip, so I got separated from them. I didn't find them or our other training partner (let's call him Speedy) before the start. There were several hundred runners, and we all were pretty close-packed on the narrow dirt/rock trail at first. I figured that Flash, Mer and Speedy would catch up to me at some point, and I saw them at a mini-turnaround point a couple of miles in, but unfortunately we never ended up running together. As Flash and I discussed later, though, for this kind of run it is actually really crucial to run at your own pace. and not to worry about running faster or slower to stay paced with the people near you. Even a 10-15 second difference can really change your gait and make it that much harder for you to get to the finish.

The race itself was very strange in some ways. The trail is basically a long path which follows the canal, and there were few enough racers that we basically all thinned out over the course until there were sometimes several minutes between people. It almost felt like I was the only one out there at some points, but there were one or two people who were running at about the same pace as I was, so we basically played leap-frog for most of the race. For the most part, however, I felt like I was going solo with only my music for entertainment.

I'll admit, it was sometimes very difficult to keep myself motivated. I used my trick of compartmentalizing the running segments (i.e., "Only three miles to go before 10, then you're halfway" or "Two more miles until the next water station") because allowing myself to think about the fact that I still had an hour to go after running for two and a half hours would be mentally crippling. The path was also very rocky, and my running shoes are reaching the end of their lifespan, so I felt sharp edges through the soles pretty much the whole way.

By the last five miles, I was starting to feel pretty bored. I wasn't exhausted, or at least I had convinced myself that I wasn't, but I was reaching the limit of mental fatigue. By the time I had passed the 17 mile mark, which is the farthest I had ever run, I just wanted to be done. I had started to speed up my pace by then, and I ended up powering in the last couple of miles at a half-minute faster pace than my overall average.

Mer was waiting for us at the finish, seemingly not that tired. As we waited for Flash and Speedy, she told me "You did it! Now you can do the marathon, no problem!"

I just shook my head, pointing out that another hour of running on top of that seemed insurmountable. Mer didn't listen to my defeatist attitude, however, pointing out how fast I was running in at the end. She said I probably had more 'juice' left in me than I realized, so I suppose I'll have to take that one one faith. Flash came in a few minutes later (he had gotten a second wind at about the 13 mile mark), and Speedy came in a few after that.

I felt a huge difference between my recovery from the 17 mile training run and the 20 mile race over the next couple of days. I'm not sure what it was in particular; whether it was breaking "the wall," or because I ran at a faster pace. Whatever the case, I got home, showered, and curled up in a ball under the covers (I couldn't get warm) and slept for hours. I had, unfortunately, made more plans that weekend, thinking that I would feel better than I did, and I had planned to attend a friend's birthday party that night starting at 10 pm. I also had hiking the next day. I ended up doing both and had fun, but it probably stretched me too thin. As Flash has said, I need to take my own advice and rest more.

We have only three more weeks of peak training (culminating in another 20 mile race) and then we start to taper for the marathon at the end of October. It's getting so close, yet a month and a half is still a pretty long time. I feel like I am really pretty ready for it at this point, so more fitness is just icing on the cake.

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