Monday, November 25, 2013

Predicting Your Duncan Ridge Trail 50km Time

Congratulations to all the DRT finishers this past weekend! I meant to get this post out before the race to provide you with something to talk about with your friends and family on race day, maybe even encourage you to shoot for a faster finishing time. Yet time got away from me.
What follows is an analysis of finishing times for runners who have finished both the StumpJump and the DRT 50km races.
Given how fast you ran the StumpJump, how well should you expect to do in the DRT? Someone recommended adding two hours to your StumpJump time, but is that true? Let's look at the data. Taking all the finishing times for those runners who have finished both races, averaging their results if they've run more than once, we plot DRT time versus StumpJump time. Stumpjump times are on the X axis (independent variable), DRT on the Y axis (dependent variable). Although the DRT 2013 results are in, let's look at how good a prediction adding two hours to your StumpJump time stacks up against a linear model prior to 2013. What's a linear model? Simple, try and draw a straight line on a plot that goes through each of your data points. That's a linear model ;) Obviously this doesn't work if your data are not already in a straight line, but try and draw a line through the oval shape that closely resembles your data. That's a linear model, too :) Unfortunately as you'll see below, sometimes the shape of your data is weird. That's when your linear model doesn't really characterize your data, and using a linear model just becomes useless.
The two hour recommendation is the red line, while the linear model recommendation is the blue line. All those dots represent runners who have run both races, their average StumpJump on the X axis, average DRT time on the Y axis. If you want to predict your own DRT finishing time, start by finding your StumpJump time on the X axis with your computer mouse, scroll up to either one of the lines, then scroll to the left to get your predicted DRT Time.

So given StumpJump times for all years including 2013, and given DRT times for all years except 2013, we see that the linear model predicts DRT times less than two hours plus StumpJump time. But our data look funny, and the linear model is probably not be a good predictor.

StumpJumpTime TwoHours ModelRec Difference
04:00:00 06:00:00 06:09:43 -09:43
04:30:00 06:30:00 06:34:28 -04:28
05:00:00 07:00:00 06:59:14 46
05:30:00 07:30:00 07:23:59 06:01
06:00:00 08:00:00 07:48:45 11:15
06:30:00 08:30:00 08:13:30 16:30
07:00:00 09:00:00 08:38:16 21:44
07:30:00 09:30:00 09:03:01 26:59
08:00:00 10:00:00 09:27:47 32:13
08:30:00 10:30:00 09:52:32 37:28
09:00:00 11:00:00 10:17:18 42:42
Now let's look at the DRT 2013 finishers who've also run the StumpJump.

At least for 2013, the two hour recommendation looks like it characterizes the data pretty well, although you could probably get away with recommending adding only 1.5 hours instead of 2.
And finally let's add the DRT 2013 finishers to our original data and see what our linear model does.

It seems to characterize the data a little better, but the data shape still looks funny. Maybe next time I'll investigate a different model. Regardless, here's a prediction table to use while preparing for DRT 2014!

StumpJumpTime TwoHours ModelRec Difference
04:00:00 06:00:00 05:50:40 09:20
04:30:00 06:30:00 06:18:11 11:49
05:00:00 07:00:00 06:45:42 14:18
05:30:00 07:30:00 07:13:13 16:47
06:00:00 08:00:00 07:40:44 19:16
06:30:00 08:30:00 08:08:15 21:45
07:00:00 09:00:00 08:35:46 24:14
07:30:00 09:30:00 09:03:16 26:44
08:00:00 10:00:00 09:30:47 29:13
08:30:00 10:30:00 09:58:18 31:42
09:00:00 11:00:00 10:25:49 34:11

Tuesday, November 19, 2013

The Harpeth Hills Flying Monkey Marathon: A Soul Crushing Ordeal

Super Monkey!

Why Would You Even Sign Up?

The Harpeth Hills Flying Monkey Marathon happens again this Sunday, but you don't want to know because it involves winged monkeys trying to eat you off the road while you race up and down the hills in Nashville's Percy Warner Park. Who in their right mind would sign up for this thing?!

Apparently lots of idiots. It sells out in minutes, and there's even a lottery to get in!

Rather than bore you with words, words that don't even want to be used to describe this poor race, I'll show you some truly sad plots that convey how slow these poor idiots run (read my StumpJump report if you need help interpreting the plots).

And if you seriously want to learn more, go here, here, here, or here.

Take all the finishing times, group them by number of times a runner has run, and show the difference each time. The red line is the mean.

What does this tell you? No matter how many times you run Monkey, you'll get slower. On average.

Monkeys Win!

The Harpeth Hills Flying Monkey Marathon: Course Profile

The Harpeth Hills Flying Monkey Marathon happens again this Sunday,

Notable Ascents and Descents (kilometers)


Start End Distance Average Grade
2.05 2.95 0.90 -0.04
10.90 11.40 0.50 -0.05
15.85 16.55 0.70 0.07
17.05 17.95 0.90 -0.06
21.80 22.40 0.60 -0.06
24.30 25.15 0.85 -0.06
28.85 29.45 0.60 -0.05
29.45 29.95 0.50 0.06
31.85 32.45 0.60 -0.02


Course Profile Every 5k

Thursday, November 14, 2013

Duncan Ridge Trail 50k Course Profile

Trolling through UltraSignup's Southeast races, I found the Duncan Ridge Trail 50k/30k and it looks spectacular! Here's the description from UltraSignup:

The Duncan Ridge Trail 50K/30K will be one of the toughest 50Ks in the Southeast with more than 10,000 feet of elevation gain. The actual elevation profile is displayed in the logo, but that is just the “out” of an “out and back” race. This race uses the Coosa Backcountry Trail and the Duncan Ridge Trail, which is considered one of the toughest trails in Georgia. The race will start and finish at Vogel State Park's Lake Trahlyta in the beautiful North Georgia Mountains. There will be a 30K option as well. If you think you're tough enough, sign up April 1st!

They may have a few spots left for this year's November 23rd race, so head on over to UltraSignup if you're feeling brave.

The plot below compares the course profiles of the DRT, the StumpJump, and the UpChuck, along with notable ascent and descent sections colored in red and blue.

Click on it for a larger view.

drt-elevation

Whoa! The DRT course profile puts the StumpJump and even the UpChuck into a new perspective! This Tennessee boy might have to mosey on over to Georgia next year. I'd go this year, but I've already started my StumpJump 2014 training (up to 20 miles a week, wohoo!).

Also, here's a few tables listing ascents and descents corresponding to those red and blue triangles on the plot. I've only included climbs that are longer that 2000 feet containing at least one section of greather than 10% grade.

DRT

Start End Distance Average Grade
0.59 1.30 0.71 0.11
1.30 1.96 0.65 -0.05
2.39 3.23 0.84 -0.11
6.00 6.52 0.53 0.19
6.68 7.18 0.50 0.23
7.64 8.51 0.87 -0.16
8.76 9.23 0.47 -0.10
10.04 10.87 0.84 -0.08
12.37 12.83 0.47 -0.23
13.05 13.45 0.40 0.20
14.51 14.94 0.43 0.12
15.35 15.81 0.47 -0.12
16.65 17.24 0.59 -0.17
17.46 17.93 0.47 0.24
21.81 22.62 0.81 0.18
23.12 23.61 0.50 -0.25
23.77 24.30 0.53 -0.19
26.19 26.59 0.40 -0.16
27.28 27.84 0.56 0.11
28.92 29.70 0.78 -0.10

StumpJump

Start End Distance Average Grade
4.54 5.10 0.56 0.14
10.25 10.78 0.53 -0.06
15.16 15.66 0.50 -0.03
22.59 22.99 0.40 -0.11
23.83 24.26 0.43 -0.12

UpChuck

Start End Distance Average Grade
12.49 12.92 0.43 0.23
12.92 13.55 0.62 -0.10
24.70 25.26 0.56 -0.08
25.51 26.25 0.75 -0.11

Friday, November 8, 2013

Predicting Your UpChuck Time with Your StumpJump Time

Over on Upchuck's Facebook page, the organizers commented that a good rule of thumb for average runners is to add 30-40 minutes to their StumpJump time. So, using the finishing times of both races (thanks again to UltraSignup) I created a very simple prediction model with a table and plot below. I found all runners who have finished both races, averaged their times, and ran them through an OLS model. If you want to see what a real statistician can do with this data, check out Dr. Chris Fonnesbeck's analysis for something a little more stringent (much thanks to him as he's mentoring me). I am showing you the results of my prediction model below as it's a little less intimidating, and it bears very nearly the same results as Fonnesbeck's.

I wish I had more time to spend on this, but I've run out and I wanted to get it out there before the race tomorrow. Head over to the Facebook page if you want to add to the discussion.

Prediction Table

So the table below has two recommendations. I call them DirectorRecommendation and ModelRecommendation. I've simplified the Director's recommendation to add 40 minutes as it gives you the more conservative estimate rather than the 30-40 minute range. So for example, if you've run the StumpJump in a time of 4 hours, the Director expects you to finish in 4:40 while the Model expects you to finish in 5:00. Interesting, a difference of 20 minutes. As you continue reading down the table, you'll see that for a StumpJump time of 5:30, both the Director and the Model agree that you will finish in about 6:10, no difference. Reading further if you finished StumpJump in 8:00, the Director expects 8:40 while the model expects 8:05.

StumpJumpTime DirectorRecommendation ModelRecommendation
04:00:00 04:40:00 05:00:46
04:30:00 05:10:00 05:23:51
05:00:00 05:40:00 05:46:57.1
05:30:00 06:10:00 06:10:02.3
06:00:00 06:40:00 06:33:07.5
06:30:00 07:10:00 06:56:12.6
07:00:00 07:40:00 07:19:17.8
07:30:00 08:10:00 07:42:22.9
08:00:00 08:40:00 08:05:27.11
08:30:00 09:10:00 08:28:32.12
09:00:00 09:40:00 08:51:37.14


Plot

The DirectorRecommendation is the red line, while the ModelRecommendation is the blue line. Start by finding your StumpJump time on the X axis with your computer mouse, scroll up to either one of the lines, then scroll to the left to get your predicted UpChuck Time.

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Tuesday, November 5, 2013

UpChuck 50k 2013 Pre Race Report

UpChuck 50k Logo

I hate throwing up. I first did it when I was sick with the stomach flu as a kid, and large food chunks got lodged in my nose and the stomach acid turned my teeth to chalk sticks. It was so gross and disgusting I vowed I would never, ever do it again. Tequila fooled me into doing it again in college, so I learned not to say never.
Emetophobia is the irrational fear or anxiety of vomiting… I'm not afraid of it; I loath it. So I think I don't have emetophobia. Maybe there's a bunch of ultra runners who have it, maybe not, but puking seems to be a rite of passage for some. And for others it's even glorified.

I'm not sure that's what Chad Wamak (watch the video. don't worry it's clean) had in mind when he and Matt Sims ran the Three Gorges section of the Cumberland Trail, but that's what Rock/Creek has done in naming it's UpChuck 50k Trail Race., being contested this Saturday, November, 9 2013.

Here's their description from their website:

Wild Trails and Rock/Creek present the official UPCHUCK 50K! The event consists of a point-to-point trail that runs entirely on the technically-challenging single track of the Cumberland Trail.

This course has huge climbs and huge descents into Soddy Creek, Possum Creek and Rock Creek. It will, without a doubt, go down in the race log as one of the best 50k courses you will ever do. Please do not attempt this run as your first 50K. This is a serious endeavor and will quite possibly be your slowest 50k to date.

Let us reiterate: this is seriously difficult. It is REQUIRED that runners have completed a 50k within the last 12 months in a time of 7:30:00 or less.

Proceeds benefit Wild Trails, a 501©(3) organization dedicated to the use, expansion and promotion of trails in greater Chattanooga.

Man I wish I could run this. Unfortunately my 8:30 StumpJump time this year leaves me outside the qualifying time.

What follows is a brief report with plots and commentary similar to my StumpJump50k report.

Number Of Finishers

The Upchuck 50k has been contested each year since 2008, with 2009 having the most finishers. Only 5 women finished in 2008 and 2012. Since the numbers are so low for women, I've also provided raw data in table format as they are hard to read from the plot.

groups 2008 2009 2010 2011 2012
Men 18.00 50.00 37.00 38.00 51.00
Women 5.00 10.00 11.00 6.00 5.00
Total 23.00 60.00 48.00 44.00 56.00

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Finishing Times

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In 2012, more men finished between 6:00 and 6:30 hours than any other half-hour time frame. Compare that to 2012 StumpJump results where more men finished between 6:30 and 7:00 hours.

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The above holds true for all years as well, and that's for both races! It has been said that if you've run the StumpJump and you're going to run the UpChuck, then add 30-40 minutes to your StumpJump time for a good estimated finishing time, but I do wonder if that is true. Maybe you should SUBTRACT 30-40 minutes!

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And look at the mens' median values (thick black horizontal bar in the boxes) trending downward! Will we see that trend continue in 2013?

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Age

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No age data was collected for 2010 finishers.

Age Groups

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