The most important thing I've learned since my first marathon is that the feeling of agony felt from 30 kilometers onward is avoidable. It took me a few tries to figure out how and ever since, my times have decreased along with the total pain and effort that comes with running 42.2 kilometers.

During my first Prague International Marathon, I felt great during the first half. The weather was perfect and festive atmosphere in the city was a motivating boost. From kilometers 21 to 30 I slowed a bit, but still felt confident about having a strong finish. The route at the time involved a long, uninspiring stretch along an open road south of Smichov and at some point on the return trip to the center my confidence disappeared.

This experience of "hitting the wall" was especially frustrating because no amount of effort would have allowed me return to the pre-wall level. Though I exerted more effort, my pace slowed and every step was laborious. The comfortable bouncing rhythm was replaced by steps that seemed to completely lack momentum. My legs felt like blocks of concrete. The notion of having a second wind to carry me through the last few kilometers was clearly not going to materialize.

The result was a finish in 3 hours and 36 minutes. Upon examining my times for the various legs of the race, it was clear just how much I slowed during the final 10 kilometers. I was happy to have completed my first marathon, but immediately set out to improve on the result. I improved a little each year and, for my sixth Prague International Marathon in 2010, crossed the finish line in 2 hours and 47 minutes.

These days, my approach to training, eating and hydration are all different. For my first marathon, I simply trained by running long distances at the fastest comfortable pace. I've since discovered the benefits of interval training and owe most of my improvement to this sort of mixing it up.

Eating carbs is a well-known necessity for all runners, but even in this area there are important differences to learn. In short, I've learned all carbs aren't the same. Having enough fuel at the time of the race is essential to avoiding agony during the latter stages.

Hydration wasn't something I thought about much during my first marathon but, had I done so, could have delayed or even prevented hitting the wall. Instead of merely drinking during the race to replenish fluids, I now start hydrating a full day earlier. During the race, I use sponges at every opportunity, and "run through" showers when available, as a way of keeping my body temperature low and thereby avoiding excessive loss of fluids.

For me, the marathon is still work in progress and 2011 is no exception. Though I enjoy races of other distances, both longer and shorter, the Prague International Marathon is my primary race each spring. When the race is planned well and prepared for, the final stretch down Parizka is one of the most enjoyable kilometers of the year.