Is a metric wheel an accurate measurement tool for a cross country course? What is the best method?
Is a metric wheel an accurate measurement tool for a cross country course? What is the best method?
dukerdog wrote:
http://ocrs.wlu.edu/Images/whyOCRS.pdf
Thanks a great study!!
Why not a steel tape? I would think it is less prone to streching with use and even the heat expansion thing would be much less than variation in a cloth tape.
Good study.
I do think they should have used a longer distance for their calibration course. Plus, there is a chance for greater error just from fatigue as one pushes the wheel along the course.
All xc courses should be taped. It does take time- but well worth it!
David Katz wrote: All xc courses should be taped. It does take time- but well worth it!
David - I'd be interested in hearing why you say this.
That study is totally bogus. First of all, a measuring wheel is NOT a standard for measuring cross country courses. To the contrary, a wheel is NOT recommended, as it can wobble side to side, bounce, and has no consistency.
The calibration course length should be at least an 800 meter straight, that has been measured at least twice by two people using a steel tape. A steel tape is a good way to measure a straight, but is NOT good for measuring a course, because it doesn't account for undulations and curves, and there is a greater chance of errors in adding up the various measurements.
The standard for measuring running courses in the U.S. is the Jones Counter and calibrated bicycle method. A road or touring bike is usually used for road courses, but a mountain bike with good treads is probably better for a cross country course, and only measure the course when it's dry and the grass has been cut. The course should be measured several times, to verify the measurements are correct and consistent. The measurement that shows the shortest course length is the one that is used.
An expensive alternative is to carefully survey the course, but I am not sure that this method is financially practical. However, it might have been used at Wisconsin in laying out the course. The Wisconsin course also uses caulk the entire course to fence off the course from the 'off course' portion. In the race, they guys were running right up to but not over the line. That course also has the advantage that outside the line the footing declines and so running some steps there would not necessarily help. Of course, Terre Haute has some fences that keep runners from cutting further in, but it is unclear exactly were you can run (several feet out is the minimum foot plant on a curve). The comment above indicates that the distance is from the middle of the course, this means that the leaders and stragglers run less distance than those in the pack, although the pack affords reduced wind resistance. This works best when the curves are gentile, I think.
800 meter calibration course? I don't know of a measurer who uses one over 500 meters since Ted Corbitt back in the 60's. "using two people?". It's tough to do it by yourself!- but it can be done!:)
You will have the same issues plus more using the calibrated bike method (Jones/JR counter).
Get a crew out there with a steel tape measure, place stakes in the ground every few feet to measure your turns and tangents, keep two sets of notes, check your calculations, Then do it again. It will take time and work.
I'm available, but not cheap!
Curves have religious biases?What exactly makes a curve Jewish and unaccepable?
26mi235 wrote:
[quote]J.R. wrote:
This works best when the curves are gentile, I think.
Fran Dreschner wrote:
Curves have religious biases?
What exactly makes a curve Jewish and unaccepable?
26mi235 wrote:[quote]J.R. wrote:
This works best when the curves are gentile, I think.
Yes, I thought about that spelling as I was about to post and then it was too late - thanks for catching my error.
genteel might be a bit of a reach but the elegant or graceful in shape,appearance or manner meaning could be used.
26mi235 wrote:
Fran Drescher wrote:Note no N in her name---Curves have religious biases?
What exactly makes a curve Jewish and unaccepable?
Yes, I thought about that spelling as I was about to post and then it was too late - thanks for catching my error.
The Jones Counter is NOT accurate unless you can maintain precise speed throughout the measurement process, just like most wheels that CLICK at each revolution. Get a continuos gear driven wheel, practice keeping the wheel stable and call it good - it\'s cross country and place prevails. Also of note- there are different rules/procedures for NCAA/NFHS/USATF - resulting in three different distances for the same course just based on procedural differences depending on the governing body of said event. In the end, everyone will love your event/course if they run fast so make it short!
avocado wrote:
Is a metric wheel an accurate measurement tool for a cross country course? What is the best method?
Garmin 305
Jones Counter Critic wrote:
The Jones Counter is NOT accurate unless you can maintain precise speed throughout the measurement process, just like most wheels that CLICK at each revolution.
That is total hogwash. The Jones Counter is the standard for course measurement and certification. You do not need to keep a precise speed. The counter does not click.
There sure are a lot of stupid people in the world, who have opinions about things of which they know nothing.
[quote] Get a continuos gear driven wheel, practice keeping the wheel stable and call it good[quote]
Again, a wheel is NOT ACCURATE. If you're doing to do something like that, there are many ways to check a course and get a false reading.
Jones Counter Critic wrote:
That study is totally bogus. First of all, a measuring wheel is NOT a standard for measuring cross country courses. To the contrary, a wheel is NOT recommended, as it can wobble side to side, bounce, and has no consistency.
The Jones counters that I have used have many counts per revolution, it is not ticking over at individual counts with a mechanical flange like bikes used to use years ago.
Then what is that clicking sound that MY JONES COUNTER makes at every revolution of that round thing on the front of my bike??? What are those two round things on my bike called again??? One is attached to the fork and the other to the frame. I bet tire pressure has nothing to do with accuracy of Mr Jones Counter either.
You don't really think the Badger course is a good example of a well measured course do you? And doesn't the caulk stick to your spikes? Or is that how they tell if you cut the corners?
How many counts do you get out of each revolution? It is not ticking some peg over once a revolution as the counting element, the numbers are 'analog' not digital and are continually moving, at least the ones that I used (it has been a while).
I cannot weigh in on the issue of using if over a grass and dirt course.
As for the Zimmer course, the last two km are net downhill and were probably net down wind at the addidas meet. No one that I remember was talking about the course being short last year and the markers seem to be in the same places as before. Overall, the times do not seem to be unreasonably fast compared to various races -- Oregon (although the women's course is short probably), PreNats, etc.
I* must say that there is a huge contrast between how the PreNats course looked and the UW course. Ask people that raced both and see what their opinions are.
Jones Counter Critic wrote:
Then what is that clicking sound that MY JONES COUNTER makes at every revolution of that round thing on the front of my bike??? What are those two round things on my bike called again??? One is attached to the fork and the other to the frame. I bet tire pressure has nothing to do with accuracy of Mr Jones Counter either.
Nuts?
The tires should be fully inflated.
The bicycle is calibrated before, and after the measurements of the course. The most conservative calibration is the one that is used.
I use a 200 meter calibration course to measure my practice courses. I have ridden 10k race courses and come within 3 counts with repeat measurements, and consistently within 1/2 count for repeat measurements of one mile training loops.
The counter is placed on the front wheel of the bicycle, there are 20 counts for each revolution of the wheel, and each count represents approximately 4 1/4 inches.
The measurement of a XC course is not really that important. What is more important is the use of the same course over many years to be able to compare times. Of course you have all sorts of variances such as weather and upkeep, but I would rather compare times from many years on the same course than try to compare times from different courses.