Bob's better results: Sawmill 15k

I've been on my training program for 36 weeks and it's time to begin assessing the progress...
  After plotting several races, I've noticed that they all seem to look similar: most of the skiers finish at rather consistent intervals (the almost straight part of the graph) with a few stragglers at the end (the rising tail). I'm not sure why the plots take this form. If each skier went at his own best pace and we had a gaussian distribution of paces, I would expect to see an "N" shaped curve with tails at both ends. Perhaps this just shows that we don't have any world class elite skiers in the local races. Also, a plot of log(t) would show the "N" of a gaussian distribution better - maybe that's a more appropriate way to graph it.

But, I digress. The point is that I was obviously in the stragglers' tail of last year's Sawmill 15k. This year, I've moved about a third into the straight part of the graph. What's more, instead of last in my division, I beat 4 men and moved half way to Leland (whose finish this year is almost identical to last year).

The absolute time isn't really important, by the way. Although I cut 30 minutes from last year, the entire field skied faster this year. Last year we all struggled with soft, punchy, slow snow. This year, the snow was firm and faster.
 

my place in last year's race
 

As you can see, the Senior Male 40 to 49 division is a pretty tough crowd, finishing 10 of the top 20 overall of the 2003 race and 8 of the top 20 in 2002.

doing a bit better this year

So, what have we learned?

What did I do better?

What did I do worse?

Here are the heart rate graphs:
 
2002
2002 sawmill race heart rate
2003
2003 heart rate