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First post here. I'm fascinated by honest efforts to most accurately measure cross country courses. I am familiar with John Tucker's cross country measuring recommendations. In short, that involves pulling a standard tape (not necessarily steel) around the course in a two person effort, flagging every 50m, laying it along the curves as needed. This is in contrast to using any wheeled device, particularly not a click wheel. Video available from his site. I do wish he'd post the video to YouTube. Perhaps I'll call him back and ask...
Re Quail Trail 5Km, apparently USATF is now allowing certification of cross country courses. And for more than the "one day" some of you folks have discussed.
Map indicates the course is mostly dirt, gravel, and grass. According to an event flyer and the event webpage, "Running surfaces include pea gravel, grass, dirt, red-clay and asphalt. Course is USA Track and Field Certified (GA09026WC)."
For those inclined, many photos from the event were posted here.
I haven't scoured the USATF certified course list. Should I assume this isn't the only off-road course now granted a USATF number?
John Kalin
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Jay - If I accurately document a course that uses rugged Forest Service roads, I still don't think I should certify it. There is too much slippage of the wheel on the very loose surface, and when bouncing over rocks (uphill or downhill), there is even more inaccuracy.

I would be interested to hear what others think about certifying a course where the surface prevents repeatable measurements. I don't think I would be within the .0008 variance on some of the rugged courses I used to measure. I only did them for an "accurate" measurement, but could not get within the .08%, so I dind't turn them in for certification.

If they can't be measured twice to within .08%, they can't be certified, correct?
I would agree that if you ride the course three times and don't have two rides within 0.08%, then you shouldn't attempt to certify the course.

I've measured numerous courses that include sections on crushed limestone paths and a couple that include dirt or grass trail sections but I haven't had that happen yet.

My question is if we don't measure and certify these courses, who will? Even given the shortcomings of the calibrated bicycle method on other than hard surfaces, I'm convinced that method is as accurate as any other with the exception of the steel tape. If we require a steel tape to measure any course that isn't entirely on a hard surface, and require that it be measured twice, very few of these courses will be measured.

Furthermore, these courses will be checked:
    using the same method that was used to originally measure them
    only if a record is set


I think I'm comfortable with that.
The much bigger issue for cross-country/off-road courses, as we all know, is the definition of the course. Once you say that cross country courses can be certified, courses with complete measurements and beautifully drawn maps saying this turn is defined by the line of cones I put down and that turn is defined by the red flags, will show up in our mailboxes. And of course, we'll have to say sorry, all that work you did is nice, but I can't certify the course.

I'm afraid that no matter how many qualifiers we put on the certification of cross country courses is now okay statement, this will still happen.
So, are there certain parameters that define a "cross-country" course as opposed to an "off road" course as opposed to a "road course with an off-road segment"?

I measured a course this past weekend which is intended to be a snowshoe race the last weekend in January. If there isn't enough snow, they'll have a running race. If there is enough snow, the surface will be snow. The course starts and finishes across a large grass field like a cross-country course would. Most of the rest of it consists of segments on well-defined gravel, crushed limstone, and asphalt walking paths, but there are a couple of shortcuts across grass areas.

I think I can define the course. I don't see any reason why I shouldn't certify it. I wouldn't feel differently if someone else had measured it.

I think we should be quite pleased that event organizers are aware enough of the advantages of having an accurately measured course that they contact us for our assistance on events like these.
Jay has good points. If the course can be ridden in a repeatable fashion, and the turns can be easily identified and used, then this is a good situation for a certification.

The question still remains, though - at what point (absolute distance, or percentage of course) do we need to be calibrating on the course's predominant surface, and not pavement? I know courses will be long if calibrated on pavement then measured on grass and gravel, but aren't we still interested in accuracy? If a 5k X-C course tapes-out to 5250 meters, it is "at least 5k". But, it's 5% long. Are we good with that?
I wonder what experiences measurers have had with measuring off-road courses repeatedly? I have in fact been quite surprised to find very consistent results over some of these non-standard paths. That would include DC's main cross-country venue, with a lot of paths through the woods, and other parts of the course defined by "key points" that are easy to lay out. Also a number of courses along the C&O Canal, a mixed dirt and gravel surface;and courses in various parks in the area. Based on my experience I would side with Jay, that we are justified in going ahead and measuring such courses,IF we can lay them out in a repeatable way.
As to Duane's point about calibration:I think it's a good idea to lay out a cal course on comparable surface. I've done this for the C&O towpath. But if it's not convenient I don't think that's a deal-breaker.
I am with Jay and Bob on this.

I recently measured a 5K/10K XC course that is 90% on a well-defined and well-bordered path. The grass surface was mowed as close as a golf course fairway and the ground was dry and firm when I measured. Where the course route traverses an open area, I identified this segment as a straight line connector between two readily definable inflection points. I steel-taped an 800 foot section in an open grassy area here and I rode it a few times to see if I was off. There was no variation. The race went off without incident of any kind. I have great confidence that this course is accurate, and that it will be easy to "re-create" the exact route for next year.

I measured another 5K in a park where the route necessarily traversed several open areas. Only about a third of the distance was on a single-track path. This course required a huge amount of work to define the path, measure the path from fixed objects, show the direction between fixed objects, and document all this. The most work of all was creating all the map insets to illustrate the route with all these additional measurements. Having said all this, I believe this exact course can readily be recreated from all this data and the map insets next year.

For me, the bottom line to certifying off-road courses mostly comes down to whether my client is willing to pay me for the additional work - for me, about double the time for a comparable road course in the two examples above. The other big consideration for me is the condition of the surface on which I am measuring. If it is soggy or muddy, if the grass is long, if there are lots of steep hills, stream crossings, small rocks and roots and such, I believe I would want to calibrate on local surface that re-creates the course conditions as closely as possible. It seems to me that for any stream or gully that is "jump-able" by anyone, the tape measure should be used to record the straight-line SPR over the obstacle. I would guess this is what is normally done in any off-road measurement. Am I right?
As discussed, certifying an XC course is a huge amount of work because of all the documentation needed to recreate the exact measured path. Two RDs who wanted a certified course in the same park for her respective events pooled their resources and hired me.

I marked the route using ~ 50 engineer's flags for the measurement. I will do the course layout on race day, using another 50 or so flags for the runners. Course marshals will direct runners to the "longer" side of the flags. There are no places where runners could cut the course short when they stay on the appropriate side of the flags.

This was a big job. The fee was nearly twice what I charge for a road 5K. I feel the course data is clear and accurate enough to support future races here when any careful race worker performs course layout. Comments welcome.
Last edited by pastmember
No, it's for real. Still working out the numbers for certification. Looks like I may need to measure one more time just to be sure. The hardest part was trying to estimate where the T/A would be in advance. Too much work, but, it is for two worthy charities...

Thanks for the compliment, Bob. And for all your good mentoring over the years.
Let me jump in here, I think I advised Lyman to do this with a different course. My reasoning is this: rough-surface cal course seem to consistently produce lower constants (see Mike
Sandford's research in this area). So an off-road course measured using a road cal course is very unlikely to be short. It might be too long for our taste but not grossly too long.

I gave an example of this with calibration numbers before, and I will look up the reference and also the information from Mike Sandford.

By the way this applies to pneumatic tires. For a while in the 80's I was using a non-pneumatic tire and I discovered that it had a reverse effect (i.e. it gave more counts on rougher surfaces).

I agree that it is preferable to lay out a cal course on the same surface you're measuring on the course but I'm just saying I think it's ok to do a road calibration and an off-road measurement.

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