You think you've just run a Personal Record time at the local 5K, but when exiting the chute you hear, "that course has got to be short". (And it's possible that the same race elicits "that course is definitely long".) Or, you're set for a good race and hit two miles just ahead of goal pace. Unfortunately, the splits for the two indvidual miles differ by a minute each and by the third mile, you've lost all faith in ability for the day.
Would a race director ever announce their course distance as "about 5 miles"? Of course not. Yet a surprising number still do not take the time to determine that their route is indeed accurate.
How accurate are road race courses? If a course is not certified, less accurate than one might think. Believe it or not, some race directors just don't care. Other courses are accurate to a director's own standards and "close enough". One race directo r said his course was "pretty accurate" based on comparing the winner's time to a previous week's race time. Another comment - "I figure 40 or 50 yards either way is pretty accurate".
A good number of directors tout their course as "USATF certified" (formerly TAC). This is the mark that runners should look for to know they have covered the advertised distance.
"Certified" means a course has been measured to exacting standards and is at least the stated distance. While no method is infallible, guidelines for certification have been developed over the two decades with the input of many technical minded contribut ors with a running background. The key is standardization - all certified courses use the same procedures for measurement and can be accurately compared.
Courses must be certified to be eligible for any type of age group record, and any runner's PR is only as good as the course being certified.
NOTE: Certified should not be confused with "sanctioned" which relates to conduct of a race and provides USATF third party liability insurance for an event. Sanctioning must be done annually; Certification is done once and is good for the life of the cou rse.
It does not take a paid expert to measure a road course; anyone with a sense of precision and ability to follow directions can do the measurement. It simply takes a bicycle, a "Jones Oerth" counter (available on loan from the USATF New England office) and a few hours of time to ride the course and complete several pages of forms.
Naturally, paperwork for the first course or two will be very scrupulously reviewed by the national certifier - in the case of Massachusetts and Rhode Island courses, this individual is Ray Nelson. Ray will return the paperwork with necessary corrections , suggestions, and comments on how to improve one's measuring work.
A car's odometer might get to within 1/10 to 2/10 of the stated distance simply because that is as accurate as such a device can be. Bicycle computers get even better precision, now down to 1/100's of miles.
A surveyor's or measuring wheel does a good job getting to a few yards or meters, but walking the wheel doesn't produce good straight lines and there is wobble side to side which exagerates the measured course length.
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 "coun ts" 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 Preventiona 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 cornor. 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.
These restrictions must be marked on the course map, and more importantly, the markers have to be in place on race day - one potential US record was lost due to cones not being in place at a 1996 championship.
Because a rider follows the SPR, measuring is best done early on a weekend or holiday morning to avoid traffic so all tangents can be cut. The assistance of a vehicle driving behind the measurer is comforting.
Note that every course does not need to be certified and some are in fact "uncertifiable" - running through parking lots and over roadways which cannot be monitored. Other races such as Falmouth or Manchester Thanksgiving are traditional non-standardized distances.
New races may need the first year or two to determine if a start or finish location can handle their field. What looks like a fast or scenic finish when setting up a course may be too narrow and crowded when several hundred runners are walking through th e chutes. But if the course is used more than a year or two, it should be certified.
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 .00006 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. Courses cannot be retroactively certified.
For a novice doing a standard 5K, the whole process (excluding setting up the calibration course) will take about three hours. As one gets experienced, riders will be able to do this more quickly, and more accurately.
The only fee required for certification is $25, which covers review of the course and maintaining a central file of maps and information. Cerfification is good for the life of the course; a recent change is that courses must now be reviewed every 10 year s to ensure changes have not been made on the course. (Remember the story of the Boston Marathon being remeasured in the 1950's and found to be significantly short, due in most part to roads being re-built and curves being straightened.)
When runners who are paying an entry fee, the least a director can do is offer a truly accurate "record-quality" courses on which to achieve a meaningful Personal Best performance.