Thursday, November 13, 2008

From Poetry to Pace Charts

OK, so I know the "taper madness" is getting bad when I start composing verse on my blog. Honestly, that post started out as just some random musings spawned on my anticipation of heading into the 5th lap at Javelina. How it morphed into a contribution to the annals of bad poetry, is beyond me. To keep such a thing from happening again, I have decided to direct my focus in a more scientific direction. Get down to business as it were--the proverbial "brass tacks" (soon to be "Brass Tax" [ed. lets not get political here]). Enough! You can see how things can get out of hand when the mind is running circles around the Arizona desert while the body is still sitting in front of a computer in a cubicle in the middle of the Silicon Valley.

I'm not sure how well known the site is. But, they do have a most excellent tool available for calculating splits and printing up a pace chart. It not only allows you to create a custom split chart for your race by defining the aid stations and even apply weighting to them based on terrain or expected slow-down due to night running, it also allows you to set three separate finish targets which I particularly like. It also has some predefined values for popular races. Some of these have weights defined for the splits based on historical data. If you are really ambitious (and have the data) you can use their "Weight Maker" tool to do this yourself. Once you have it all worked out, you can create a nice printable chart to take with you on race day.

Since I don't have detailed split data for Javelina available, I just did some estimates based on my experience and what I think I should run. I could have used my data from last year, but, as mentioned in a previous post, it is a bit skewed by hotter than normal temps and a poorly executed race strategy. I took the mileage data from the large 11x17 map at the park website. The Coyote Camp aid station is basically at the junction labeled "Tonto Tank" on the map and the Jackass Junction aid station is around 1/2 way down the 3.2 mile trail that leads to "Cedar Tank." The Headquarters (start/finish area) is at the "Trailhead Staging Area." The route sticks to the Pemberton Trail (labeled PB on the map) except for the final short loop which returns down the Tonto Trail (labeled TT) after Coyote Camp.

My assumptions for weighting is based first on the ups/downs of the terrain and then adjusted up as the race proceeds. I added an additional 10% after the first two loops and then another 10% to the more technical sections during the night. Normally I wouldn't add this much during the daytime and would expect to slow down much more at night. However, the potential heat at Javelina usually slows things down a bit extra in the middle of the day and at night I don't think you loose as much at Javelina because it cools down, it is scheduled near a full moon and the trail is pretty easy to see. You can look at my weights in the pace chart below. The first section contains my base weights so you can check out how I adjusted them for subsequent laps. The numbers actually came out pretty close to what I am targeting for the individual laps. I entered three goals of 22 hrs (lower bound), 22:40 (aggressive target) and 23 hrs (upper bound).

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