Friday, October 17, 2014

Hitting the wall ...

... in a two-mile race. What?

Couple days ago at work, I ran the semi-annual "Fun Run" that winds through parts of the Goddard campus. Though labeled as "fun," it's actually quite competitive. My first year running this was in 1997, with a time of 14:57, still my PR for the course. From 1997 to 2012, my times had ranged from 17:25 (2005) to 15:40 (2012). During this period, I mostly ran to just stay in shape. Then, in the Spring 2013 race, after having completed my first 16-week marathon training program and the Rock 'n' Roll USA marathon a month earlier, I finished the two miles in 14:59, just two seconds slower than my PR from 16 years earlier. Adaptation staying ahead of aging. :) The next two runs (Fall 2013 and Spring 2014) came in at 15:11 and 15:07.

That the average pace for 14:57 is 7:29 has been bothering me. Sure, in many aspects, shorter races (say, up to 10K) are harder to run than are longer endurance races. But, my PR paces for 10K and 5K are 7:32 and 7:23, respectively. (The 7:32 is my "modern" PR; my all-time 10K PR is 6:23. But, that's another story.) So, it's been puzzling me why I couldn't seem to go much under 15:00 for two miles. Granted, the Pikes Peek 10K course is slightly net downhill. But, the Mercy 5K course is over rolling hills and on par in difficulty with the Fun Run course, which has hills in the middle half of the first mile and in the last half mile. I figured, with the Fun Run being a mile shorter than the 5K, I should be able to go at least 8 seconds faster (7:15) and sustain that.

That was in my mind, when the race began. I don't know exactly at how fast a pace I started, but I think it was at least 7:15--and, as it soon turned out, way too fast. I was feeling good until around the half mile point and still going up the hill. Then, quite suddenly, the legs were burning, to the point that I even had a momentary thought of stopping. I didn't; but my pace significantly slowed. I had hit the wall, or at least my two-mile version of it. Obviously, only 3-4 minutes into the race, it was not a matter of glycogen depletion, as it is when one hits the marathon wall at around Mile 20. But, I was running too fast, based on my training, and the body's lactate clearance couldn't keep up with its production, resulting in the burn. I guess the principle is the same, whether for marathons or two-milers: One can't run at a pace for which one didn't specifically train--duh! Start too fast, will hit the wall, or some analog of it. Now, had I stopped and walked a bit, I would have recovered fairly quickly. But, in a two-mile race, there's no time to catch up! As it happened, I didn't stop but slowed until the burn dissipated and then picked up the pace. But, the damage was done. I finished in 16:11.

The point I keep making, mostly to myself, is that I regularly run two miles, as part of longer races or training runs, at paces that are not too far off my 7:29 two-mile PR pace. In the 2013 MCM 17.75K, Miles 6-8 were all at around 7:45. In last weekend's 18-miler, the last two miles were at 8:25 and 8:05. In recent weekly tempo runs (8 miles total), the last two of the middle four tempo miles were at 7:40. It just seems I should be able to sustain a 7:15 or faster, when the entire run is only two miles. I think the clue to why I've not yet been able to go faster is all these other two-mile paces were achieved well into the race or run, after I've had time to get into a nice rhythm, smooth and light. (See also the article, "Pace yourself.")

So, the counterpoint must be, in a short two-mile race, there's no time to get into any rhythm--unless one has specifically trained for such a distance. As for why I ran this week's Fun Run in a relatively sluggish 16:11, there are several possible "on any given day" reasons. This week is the last hard workout week of my current 16-week marathon training cycle. The day before the Fun Run was a hard workout of 10 x 90-second hill repeats (9 miles total, including warm-up and cool-down), so I was not well rested. The weather was warm and humid (near 100%). I couldn't get away from work early enough, so I'd to rush to get to the start line. There are other possible reasons, but the main underlying reason must be that I've been training for marathons and not two-mile races. The principle of training specificity!

My plan for 2015, then, is to apply this principle. I plan to skip the early spring marathon and target one towards the end of May. Before starting the training cycle for the latter, I plan to use the winter months to do more shorter-race-specific training, aimed at the spring Pikes Peek 10K and Mercy 5K, as well as the spring Fun Run. Should be fun!

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