CCM Diary: Fantasy Marathoning


My calves are still sore, though they’re getting better.  Hopefully I’ll be back to running tomorrow.

One way I occupy my mind and distract myself when I’m not running is to play with numbers.  Running is like baseball – my running generates an endless pile of stats for me to play with.

There’s a rule of thumb that says that when you start training, you can expect to see improvement for about 10 years before you reach a point of diminishing returns.  That rule fits my experience perfectly.  I started at road racing at 31, I PR’d in both the 5K and the marathon when I was 41, and now that I’m 51, those PRs are just a fond memory.

A little while ago, I used an age-grading calculator to compare last year’s marathon time to my marathon PR.  I thought it might be fun to expand on that analysis and see what else I might learn.  I took the USATF age-grading calculator and pace prediction calculators from Runner’s World and Team Oregon and plugged in my PR’s for the 5K and marathon and my times from the past year.

Here’s the chart:

The first thing I noticed is that even though I’ve put a lot more effort into improving my marathon time, according to my age-graded scores I’m better at the 5K than I am at the marathon.  If I take my times in shorter races on the track from when I was in school, I score even better.  So maybe I’ve spent the last 20 years beating my brains out working against my natural abilities by training for marathons and ultras.  Whatever.  I’m having fun, and it’s not like I was going to win any Olympic medals if I focused on short races.

My age-graded 5K score has gotten worse over the last 10 years while my marathon score has stayed steady.  I’ve got two possible explanations for that.  One is that the consistency in my marathon score might reflect all the extra effort that I’ve put into running longer distances.  The other is that I’ve always wondered if the course for my 5K PR might have been a little short.  18:49 is about 40 seconds faster than any other 5K I’ve run.  That’s a lot.  Coincidentally, if I use my age-51 5K score to project an age-41 5K time, the result is much closer to my second-fastest 5K than my PR.

The Team Oregon time predictions are much closer to my actual results than the ones from Runner’s World, perhaps because they include my age in their calculations.  Both of them are pretty far off when they’re using my 5K PR to predict an age-41 marathon time.  If I recalculate that prediction with the Team Oregon calculator using my second-fastest 5K, the projected time of 3:15 is much closer to my actual marathon time.

So what have I learned?  Three things:

  • The Team Oregon pace calculator seems to be the tool of choice for making race predictions.
  • My goal of 3:27:59 for Cape Cod still appears to be realistic.
  • I don’t CARE if the American Canyon 5K course was short.  My 5K PR is still 18:49.

(15.9 mi. bike; 146.5#)

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