That Course Was Long

[caption id="attachment_4643" align="alignright" width="231" caption="Source: Wikipedia"]jones_oerth_coutner_course_certification[/caption] On Sunday I ran the Dallas Running Club Half-Marathon and my watch when I was finished read 13.13 miles.  Extremely accurate I would say, wouldn't you?  When I was done I stayed by the finish line to wait for Karen to finish.  As I was waiting I heard runner after runner say that the course was long. I heard: That course was long.  I have 13.24 what do you have? I heard: Man I would have been faster if the course was not so long.  A 13.28 mile half-marathon? I heard:  Who measures these courses?  Seriously every one I have run was long and this was 13.22 miles....... Let's first start out by saying courses are certified by a governing body and thus are not long or short by the discrepancy that your watch is showing.  Why would a race director sell a 13.1 run and then make it 13.28?  What do they gain from that? So let's discuss running the tangents.  When you run the tangents you run the straightest line there is so you remove discrepancies from a course.  How about the fact that you are running side to side to avoid the people in front of you?  That adds the distance to your run. How about the fact that GPS units use a triangulation to 'guess' where you are at.  They don't pinpoint your exact spot and follow you.  It guesstimates where you are at over the course of that run or ride and gives you a distance that you travelled. Karen and I were discussing this yesterday because her watch showed she ran 13.24 miles and I told her that I ran the same exact course and the course measured out to 13.13 so how could she have run a 13.24 half-marathon?  It created a bit of a discussion in our house to say the least.  I gave her all the reasons above but remembered reading about how courses are measured and wanted to show that courses are neither long or short and are accurate to within 1/100th of a mile.  Very accurate wouldn't you say? You can read the entire article here, but here are the highlights from my perspective: ==================== The preferred method of measuring a course is with the "Jones-Oerth" counter attached to the front wheel of a bicycle. The counter is then calibrated over a surveyed or steel-taped 1000' calibration course. My bike and counter registers over 18,000 "counts" per mile (a counter registers different totals depending on tire size). That is just over 3 inches per "count", producing pretty good accuracy. When calculating the measurement factor for the bike counter, a "Short Course Prevention Factor" 1/10 of 1% is included in the calibration constant. This Factor gives a course that is very slightly long, adding a perceived 5 meters over a 5K. Yet, much of that can be "eaten up" by the rider swerving to avoid a pothole or a vehicle, or in doing a first time measurement. When a course is measured for certification, it is done along the "Shortest Possible Route" (SPR) that a runner can take. That is, the route is measured along the line of sight a runner has, cutting all tagents and crossing corner to corner. If a course is to be restricted in any way in meauring (such as staying to the right of the road or going wide around a turn, there will need to be monitors, fences, or cones to do so. Anyone reading this article has probably seen that you can't rely on runners to stay in the breakdown lane, or to run where they should if it is not monitored. ==================== [caption id="attachment_4645" align="alignright" width="237" caption="Source: USATF"]jones_oerth_counter[/caption]

In a nutshell, the procedure is as follows:

  1. Set up a calibration course on a flat, straight road. Once laid out and marked, this standard calibration course can be used at any time in the future. It is best set out on a lightly traveled road.
  2. Attach the counter and calibrate the bike. Every bike wheel will calibrates differently. Even changes in temperature during the day can change the constant several counts per mile.
  3. Ride the course at least twice. Use the longer of the two rides as the final ride. The rides must be within .00008 of the distance of each other, or a third ride is needed. While it may sound like a difficult precision to attain, experienced measurer s routinely have their two rides match to within 10 counts or less (about 30") even over courses 10K and longer.
  4. Recalibrate the bicycle following the measurements to be sure the constant has not changed. A change in temperature or air pressure can change the constant. Adjust the course if needed.
  5. Complete the application and draw a detailed map to accompany the paperwork. The map should allow a total stranger (or a new race director) to set up the start, finish, and race course.
  6. Send this paperwork to the certifier postmarked no later than race day, and preferably earlier. Courses cannot be retroactively certified after the date of the race.
With this tool measuring a course can we all put to bed the idea that a course was long or short?  Can we just say that we did not run the most efficient race we could have?  At 70.3 Austin I swam the 1.2 mile course in 40:08 which was 29 seconds faster than my time at 70.3 Oceanside but about 5-6 minutes slower than I had anticipated.  Guess how many miles I swam that day?  You are correct if you guessed 1.4 miles.  Now this is the perfect example of not swimming a straight line.  I had to pass people and I sometimes swam around them.  Other times (most of the time) I was not sighting well and thus was all over the swim course.  I did not get out of the water and say that the RDs created a long swim but instead took my medicine for not swimming a straight line.

Did You Know About The Jones-Oerth Counter?

Jason Bahamundi

About the Author:

I grew up in New York and lived there for 34 years until I got divorced and moved 1600 miles to my new home in Texas.  I love New York and miss it but that does not mean that Texas hasn’t been great to me because it has.  It was here that I discovered endurance sports and specifically the sport of triathlon.  Triathlon has given me new life through all the challenges it presents.  I no longer look at life the same way and I can say that is in part due to my endeavor into this sport.

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