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News Article: On River Run course, every step is measured

justinkuojustinkuoCertifier
Here's an article that appeared in the Florida-Times Union newspaper.

You can read the complete article and view the photos by going to this link.

http://jacksonville.com/sports...-every-step-measured

I included the text from the article below.

Enjoy! -- Justin

+++++

On River Run course, every step is measured
Racing course must be certified as 15 kilometers every time it changes
Posted: March 12, 2011 - 12:00am

Gate River Run
What: U.S. 15K national championship.
When: 8:30 a.m. today (8:24 a.m. for elite women head start).
Where: Start on Gator Bowl Blvd., finish on Duval Street.
More information: Go to www.gate-riverrun.com.

By David Johnson

Todd Williams turned on the final stretch in the 1995 Gate River Run, and Doug Alred had a bad feeling.

"My first thought was, 'We messed it up,' " said Alred, who has been race director since 1983.

Alred had recertified the course that year, and he was worried that a bad measurement could have cost Williams an American record.

But USA Track & Field verified the course was correct, and Williams' 15K record stands to this day.

Alred has had to certify the 9.3-mile course many times since then "including this year" but the science behind measuring gives Alred a lot more confidence.

Construction in the San Marco area led to a course change for today's race, and Alred used satellite GPS mapping to provide an initial road map.

"We can just about figure it exactly," Alred said. "The measurement [by GPS] always comes out a little longer."

The ultimate measurement comes in a decidedly low-tech way. Alred uses the industry standard, a Clain Jones Counter fitted on the front wheel of a bicycle.

"We do it with two bikes in tandem. One follows the other," Alred said. "One is supposed to be taking the shortest path possible. The second one tries to take it even closer, if he can, without violating the measurement."

The Jones Counter clicks more than 18,000 times for a single mile.

The measurement has to be done no closer than one foot off the curb, and Alred said he doubts anyone besides the leader would be able to run all the turns perfectly.

Alred said race officials only had to certify the first four miles of the course, because the rest remained unchanged.

The start line had to be moved about eight feet, but Alred said competitors probably won't "realize it moved at all."

Race officials must build an extra five feet into the course per mile before sending the certification into USATF.

USATF calls this a short-course addition factor, which assures that the race won't be shorter than the stated distance.

That means not even the best runner can finish today's River Run in exactly 15,000 meters.

Alred estimates that the course is at least an extra 45 feet long.

david.johnson@jacksonville.com,
(904) 359-4491

Read more at Jacksonville.com: http://jacksonville.com/sports...asured#ixzz1GRG6uDoY
Original Post

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duanerussellduanerussellMeasurer
I must be missing something. Every time the SCPF is described in one of these articles, it says that the course is [the SCPF] long.

I don't know about everyone else, but I know I don't ride a perfect line. Take my wobble into account, and the variance from a perfect line, and my courses are not an extra 5 feet per mile. Three feet, maybe, or even two, if it is a windy day, but rarely 5 feet.

Or, am I missing the whole concept of SCPF? If I am not off-base, we need to try to explain the SCPF to others, so people aren't thinking they are always running a full .001% long.
michaelbowenmichaelbowenMember
Duane, I think it's because most newspaper reporters try to "(over-)simplify" the measurement process, from the factors devised to ensure the course is not short to the difference between measurement and certification (FL's certifier is Everett McDowell, not Doug Alred).

I get the question all the time from race directors who ask me to "certify" their course.
M mikesandfordMember
quote:
Originally posted by Duane Russell:
I must be missing something. Every time the SCPF is described in one of these articles, it says that the course is [the SCPF] long.

I don't know about everyone else, but I know I don't ride a perfect line. Take my wobble into account, and the variance from a perfect line, and my courses are not an extra 5 feet per mile. Three feet, maybe, or even two, if it is a windy day, but rarely 5 feet.

Or, am I missing the whole concept of SCPF? If I am not off-base, we need to try to explain the SCPF to others, so people aren't thinking they are always running a full .001% long.


Duane,

I have noticed you have often said that you wobble when you measure and the SCPF takes care of that. That is not the way I think about my measuring.

Yes, I wobble a bit when measuring. But I also wobble when calibrating. If my wobbles when calibrating are the same as when calibrating there is no effect on length measured. Ok so I am unlikely to wobble exactly the same amount all the time, But do I always wobble more on measuring than when calibrating - unlikely. Or vice versa also unlikely. (Especially now that I have an electric assisted bike to help me up steep hills without wobbles)

I believe the difference between my wobbles when calibrating to when measuring could go either way, so sometimes may add a little distance sometimes subtract.

Note I am not talking about not following straight lines along the SPR, and around the bends. Years of practice and the reproducibility achieved convinces me that I follow very closely to the SPR - well within +/- 0.02%.
peteriegelpeteriegelRCMBB Founder
ORIGIN OF THE SCPF

This is my personal recollection of the origin of the SCPF. Corrections are welcome.

In the 1970’s, before USATF (then AAU) included the Road Running Technical Council, road course measurement was a one-man operation run by the late Ted Corbitt. He worked with Ken Young, the founder of road running records, who is still in the game. As they worked toward creating a credible road records system, the idea of “validation” emerged. That is, for a record to be recognized, the course must be checked, and it must not be found to be short. Around 1980 Ted decreed that, for certification to be valid, 1 m/km must be be added to the nominal course length. It has been that way ever since. Certification and records are Siamese twins, with the requirements of each dependent on the requirements of the other.

Let’s simplify what we have today, but without an SCPF:

Consider that today only two measurers exist, of more or less equally known abilities. Measurer A lays out a 10 km course at exactly 10,000 meters. A record is set. Measurer B is tasked to validate the course.

Because two measurements hardly ever agree, there is a 50 percent chance that Measurer B will find the course to be shorter than 10,000 meters.

What to do? Change the requirement to allow a record to be set on a course that validates to less than the nominal distance? This is a possibility, but one not popular with record-keepers, whose mantra has long been “A course shall not be short.”

The choice of adding on the SCPF was made to put things on the safe side. A competently laid out course, with SCPF included, will not fail its validation measurement.

There have been other proposed solutions to the problem, but the SCPF has survived.
M mikesandfordMember
The question prompted by the article Justin quoted is,

"How can we express the SCPF in very simple terms with minimum technical jargon, so it reads well in articles for the general public (with an interest in sporting matters)?"

So, building on what Pete posted, here is my attempt at a precis for the general public.

"Although using the Jones counter is the most accurate readily practical way of measuring a course length, there are inevitable small errors. These errors are allowed for by adding *5 feet to each mile* of the course. So it ensures that, if the course is remeasured, perhaps because a record has been set, the course won't be found short and any record disallowed."

*...* for a metric audience substitute "1 metre to each kilometre".

That was 63 words. Please improve.
peteriegelpeteriegelRCMBB Founder
ORIGIN OF THE SCPF

Ken Young replies

"Hi Pete,

Sorry for the delay in responding. It has been rather hectic around here lately.

To your article, in order of reading....

The AAU was followed by TAC which in turn was followed by USATF.

Ted and I talked about these matters only a couple of times. Once was when I went to New York to meet with Ted and get his approval for adding four "final signatories: to help with the workload and increase the numbers of certified courses. You were one of the four as I recall. I suspect Bob Baumel was another. I am not sure of the other two.

I was the one who initiated the validation process. I was operating thru the NRDC at the time (1980 or 1981). I managed to talk the race directors of the Jacksonville River Run and the Gasparilla Classic, both of whom were claiming the US 15K record and claiming the other's course was short, into funding David Katz to come to Florida to validate both of these courses. Both passed. Those were the first independent validations that were carried out (as opposed to a remeasurement, usually by the race organization). When Bob Hersh asked me to draft the rules for road record-keeping for the USA, I incorporated the validation into the rules.

The SCPF was entirely Ted's but one that I supported strongly. One underlying premise was that if the course were validated and found short of the advertised distance, the probability that something was wrong with the original measure would be very high. These two more-or-less independent developments came together at just the right time to form the basis of our present road record-keeping rules.

The basic precept of record-keeping is that the runner ran AT LEAST the stated distance in not more than the stated time. I also prefer the wording that the SCPF helps insure that the runner ran at least the stated distance.

I could go on and on with regard to the other posts but I don't have the time. I would like to point out that no two runners run the EXACT same route on the course and very few, if any, can actually run the SPR in a race as large as Jacksonville. The SCPF is 5.28 feet per mile, not 5' per mile. One doesn't certify the first four miles of a course; one certified (or recertifies) the entire course that may be based on new measurements covering the first four miles. The SCPF is 0.1%, not 0.001%.

These people are talking about the length of the course as if it were actually known. All we can do is put error bars on it and give it our best estimate. All we can say is that the course is most probably at least 15K. Anything beyond that is rather pointless."

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