3D.15.2 Distance Measurement for Fixed Distance Races
Comments about this discussion:
Started
The current method described in the rulebook is not precise enough to meet the requirements for WRs. This issue has been discussed with the WR committee.
For a fixed-distance race to qualify as a WR, it is necessary to measure the course before the race. Ideally, a precise official measurement should be made, but if this is not possible, a less precise unofficial measurement with a larger safety margin should be made.
This is my proposal for an unofficial measurement that is supposed to guarantee correct accuracy.
It's a simplified measurement method using a Jones Counter. This method includes the measurement of a calibration base of 300 to 500 m with a 30m steel tape, as this is essential for accurate measurement. This method is simplified because I've removed less important elements such as measuring the outside temperature and measuring the calibration base after the course measurement (Instead, I've added that you shouldn't take measurements (calibration and course) at a time when there's a big variation in temperature). The use of a correction factor of 1.003 (instead of 1.001) should make it possible to obtain a relatively accurate and conservative measurement.
3D.15.2 Distance Measurement for Fixed Distance Races
For fixed-distance races, the course must be measured accurately along the shortest possible path to ensure that the measured distance is at least equal to the advertised distance.
1. Official measurement: The course distance must be measured before the race using a Jones Counter, following the official IAAF recommendations or an equivalent method offering comparable accuracy. This measurement ensures the validity of the results and the potential recognition of records.
2. Simplified unofficial method: If an official measurement before the race is not feasible, a simplified method may be used. This method maintains a high level of accuracy and ensures a conservative measurement by applying a correction factor of 1.003.
2.1 Required equipment:
2.1.1 A certified Jones Counter, mounted on a bicycle wheel (preferably with a smooth, well-inflated tire).
2.1.2 A calibration course: a straight, flat, and stable section of road with a known precise length, ideally between 300 m and 500 m.
2.1.3 A certified steel measuring tape of at least 30 meters, used to confirm or verify the exact length of the calibration course.
2.1.4 Markers to clearly define the start and end points of the calibration course.
2.1.5 A notebook or app to record all measurements.
2.2 Steps for the Simplified Method
Calibration and course measurement must be carried out consecutively at a time of day when there is no great variation in temperature.
2.2.1 Calibration of the Jones Counter: a critical step
Calibrating the Jones Counter is essential to ensure the accuracy of all subsequent measurements. This step must be performed meticulously:
2.2.1.1 Setting up the calibration course: Choose a straight, stable section of road, and confirm its exact length using a steel measuring tape. Ensure that the start and end points are clearly marked and fixed.
2.2.1.2 Measuring the calibration course: Perform 4 measurements (2 round trips) of the calibration course with the Jones Counter:
Ride slowly and steadily along the full length of the course, maintaining a straight line.
Record the Jones Counter readings at each end for every pass.
2.2.1.3 Managing errors: If any reading deviates significantly from the others, it must be discarded. Such errors may arise from deviations in the bicycle’s path or instability. If necessary, repeat the 4 measurements to obtain reliable data.
2.2.1.4 Calculating the calibration factor (CF):
Average the valid readings to determine the calibration factor:
CF = Average number of Jones Counter counts over 4 measurements / Length of the calibration course in meters
2.2.1.5 Applying the correction factor: Apply a correction factor of 1.003 to ensure a conservative measurement:
CFcorrected = CF × 1.003
2.2.2 Measuring the course:
2.2.2.1 Starting point: Position the bicycle equipped with the Jones Counter at the starting point of the course.
2.2.2.2 Measurement: Ride slowly and steadily along the shortest possible path of the course (the "ideal line").
2.2.2.3 Final reading: Record the Jones Counter reading at the finish point.
2.2.3 Calculating the measured distance:
Use the corrected calibration factor to convert the Jones Counter readings into the actual distance:
Actual distance (m)= Total number of Jones Counter counts over the course / CFcorrected
2.3 Post-race validation:
If the simplified method was used before the race, an official measurement must be conducted after the event to validate any potential WR.
Comment
It's hard for me to see where you've simplified it. Looks more like you've summarised the method for using the Jones Counter. Have you left out anything from the IAAF method?
Comment
The principle of measurement is the same, the elements I propose to omit for simplicity are:
- no need to measure the calibration base after the course measurement
- a single course measurement may suffice (in the IAAF method, 2 measurements are required for all sections that are covered at least 2 times)
- no need to take air temperature into account in the calculations
I have also tried to simplify the instructions to the essentials and to add a calculation to easily convert a number of Jones counter revolutions into a metric distance.
I think it's important to keep the length of 300 to 500m for the calibration base, the use of a steel tape of at least 30m to measure the calibration base and the 4 measurements of the calibration base. This is the most important part of a reliable measurement.
It's certainly not a very simple method, but no method without a calibration base is reliable. In my opinion, an official measurement should be preferred before a fixed-distance race.
Comment
I like the suggestion for measuring the distance, as this would describe a procedure in the rulebook that would also be suitable for world records, as the procedure currently described definitely has its weaknesses and should not be used for records.
I am still unsure whether it would be better to use Roman numerals to number the individual steps, as the individual steps actually belong together somehow and describe the actual process (e.g. under 2.2.1 as a further subdivision i, ii, iii, iv, v).
Comment
I do not particularly want to add a couple pages that describe what is already in our world record guidelines (and therefore would have to be changed to align with future WR guideline changes). Why not simply something like “Fixed distance races should be no shorter than the stated distance and may exceed stated distance by no more than 5%. Every effort should be made to meet IUF World Record guidelines for course distance whenever possible.”
I would not be at all surprised if new equipment makes using a jones wheel obsolete in the next 5 years, as it’s not technically difficult to get good enough GPS accuracy, but the equipment that does it is currently prohibitively expensive.
Comment
> I do not particularly want to add a couple pages that describe what is already in our world record guidelines (and therefore would have to be changed to align with future WR guideline changes).
Currently, however, the World Record Guidelines do not describe how the distance is to be measured, this is done exclusively by the IUF Ruelbool in Rule 3D.15. And the World Record Committee would like to keep it so that the World Record Guidelines refer to the Rulebook and not the other way around. After all, the world records should reflect the competitive sport and the IUF Rulebook is the basis for this.
> I would not be at all surprised if new equipment makes using a jones wheel obsolete in the next 5 years, as it’s not technically difficult to get good enough GPS accuracy, but the equipment that does it is currently prohibitively expensive.
Then this could simply be added in one of the upcoming rulebook committees. After all, the Rulebook is updated every two years after Unicon, so there is a regular opportunity to adapt to current developments.
Comment
Ah, if it is our job to answer this question I support the inclusion. I was concerned that we were adding significant sections that represent doubling an effort that was being done elsewhere. I get a little concerned when I see long technical sections as they make the rulebook far more intimidating for volunteers to understand, but some are simply necessary
Comment
Perfect :)
The idea is to have the description of the measurement in the Rulebook as before and to simply refer to the Rulebook in the Word Record Guidelines wherever possible.
Comment
> I do not particularly want to add a couple pages that describe what is already in our world record guidelines (and therefore would have to be changed to align with future WR guideline changes). Why not simply something like “Fixed distance races should be no shorter than the stated distance and may exceed stated distance by no more than 5%. Every effort should be made to meet IUF World Record guidelines for course distance whenever possible.”
One of the reasons for adding this section is that it's quite difficult to measure with certainty a distance longer than the official distance without adding a lot of distance.
> I would not be at all surprised if new equipment makes using a jones wheel obsolete in the next 5 years, as it’s not technically difficult to get good enough GPS accuracy, but the equipment that does it is currently prohibitively expensive.
The Jones counter method is a recognized, reliable and inexpensive method, and it's the official method used by athletics federations, and the one that measurers are trained to use in 2025. In my opinion, this method will remain the reference for a long time to come, but it will always be possible to change the rulebook when the time comes.
I hope we'll see more and more official measurements before (fixed-distance) races, as is the case for athletics road races.
Comment
I have thought about the proposal a little more and made some suggestions for changes (inserted in bold) - I have inserted the reasons for the suggested changes in italics.
3D.15.2 Distance Measurement for Fixed Distance Races
1. For fixed-distance races, the course must be measured accurately along the shortest possible path, that means 30 cm from the kerb or other solid boundaries to the riding surface, to ensure that the measured distance is at least equal to the advertised distance.
> I think there has been some confusion in the past as to why for track races the measurement distance is 30 cm on the inside of the track, but for road races there is no distance - in fact the Worls Athletics rules stipulate the same distance of 30 cm. I would make this very clear in the rules to avoid confusion.
1.1. When ever possible an official measurement must be carried out before the race. For this the course distance must be measured using a Jones Counter, following the official IAAF recommendations or an equivalent method offering comparable accuracy. This measurement ensures the validity of the results and the potential recognition of records.
1.2. If an official measurement before the race is not feasible, a simplified method using a Jones Counter may be used. This method maintains a high level of accuracy and ensures a conservative measurement by applying a correction factor of 1.003. No records can be recognized by this measurement.
> 1.1 and 1.2 describe two different procedures that represent an either or rule - in an official measurement before the race, 1.2 is irrelevant, which is why I would express this by numbering 1.1 and 1.2.. At the same time, the rule emphasizes the relevance of an official measurement and that no records can be recognized without officiall measurment.
2. If the simplified method was used before the race, an official measurement must be conducted after the event to validate any potential record.
> I would move this part of the rule further up, as it actually belongs logically to 1.2. You could even consider adding the sentence to paragraph 1.2, as it is irrelevant in the case of 1.1 anyway.
3D.15.2.1 Simplified method using a Jones Counter
> I think adding an additional heading here will make it clearer what the following paragraphs refer/belong to.
1. The following equipment is required for measurements using a Jones Counter:
i A certified Jones Counter, mounted on a bicycle wheel (preferably with a smooth, well-inflated tire).
ii A calibration course: a straight, flat, and stable section of road with a known precise length, ideally between 300 m and 500 m.
iii A certified steel measuring tape of at least 30 meters, used to confirm or verify the exact length of the calibration course.
iv Markers to clearly define the start and end points of the calibration course.
v A notebook or app to record all measurements.
2. The simplified method using a Jones Counter consists of three steps, according to i - iii. Calibration and course measurement must be carried out consecutively at a time of day when there is no great variation in temperature.
i Calibration of the Jones Counter: a critical step
Calibrating the Jones Counter is essential to ensure the accuracy of all subsequent measurements. This step must be performed meticulously:
i.i Setting up the calibration course: Choose a straight, stable section of road, and confirm its exact length using a steel measuring tape. Ensure that the start and end points are clearly marked and fixed.
i.ii Measuring the calibration course: Perform 4 measurements (2 round trips) of the calibration course with the Jones Counter:
Ride slowly and steadily along the full length of the course, maintaining a straight line.
Record the Jones Counter readings at each end for every pass.
i.iii Managing errors: If any reading deviates significantly from the others, it must be discarded. Such errors may arise from deviations in the bicycle’s path or instability. If necessary, repeat the 4 measurements to obtain reliable data.
i.iv Calculating the calibration factor (CF):
Average the valid readings to determine the calibration factor:
CF = Average number of Jones Counter counts over 4 measurements / Length of the calibration course in meters
i.v Applying the correction factor: Apply a correction factor of 1.003 to ensure a conservative measurement:
CFcorrected = CF × 1.003
ii Measuring the course:
ii.i Starting point: Position the bicycle equipped with the Jones Counter at the starting point of the course.
ii.ii Measurement: Ride slowly and steadily along the shortest possible path of the course (the "ideal line").
ii.iii Final reading: Record the Jones Counter reading at the finish point.
iii Calculating the measured distance:
Use the corrected calibration factor to convert the Jones Counter readings into the actual distance:
Actual distance (m)= Total number of Jones Counter counts over the course / CFcorrected
> The different numbering makes it clear that these are not either or rules, but steps of the procedure that must all be carried out in this way and, above all, in this order.
Comment
"1.2. If an official measurement before the race is not feasible, a simplified method using a Jones Counter may be used. This method maintains a high level of accuracy and ensures a conservative measurement by applying a correction factor of 1.003. No records can be recognized by this measurement."
I'm not sure what the point of using a simplified method that is still complicated and time consuming, but not good enough to be recognised as a world record. Either it's good enough, we shouldn't use it.
"I would not be at all surprised if new equipment makes using a jones wheel obsolete in the next 5 years, as it’s not technically difficult to get good enough GPS accuracy, but the equipment that does it is currently prohibitively expensive."
I'm happy to be proven wrong, but looking at the GPS tracks we have currently, there are huge errors. My Lezyne GPS said I did over 5000m of climbing/descend during my 24hr record, while my phone GPS said over 15,000m. While it wasn't flat, I would guesstimate that I climbed at most 1-2m/lap.
5yrs might be optimistic. We'll have time for future Rulebook editions to change it if there is a better way.
Comment
> I'm not sure what the point of using a simplified method that is still complicated and time consuming, but not good enough to be recognised as a world record. Either it's good enough, we shouldn't use it.
I think the point is that the method described is primarily intended as a replacement for the method currently described in section 3D.15.2 Distance Measurement for Fixed Distance Races. The current method is also completely inadequate for world records and is nevertheless probably used at most competitions. With the newly described method, we would have a similarly complicated method as before, but one that is more accurate, which I think is a clear improvement for the riders because it increases the comparability of results which ist the main aspect of a fixed distance race.
> 5yrs might be optimistic. We'll have time for future Rulebook editions to change it if there is a better way.
I totally agree here - let's put what's currently available in the rulebook now and if in a few years there's another comparably accurate method that's even simpler, then let's adapt the rulebook accordingly.
Comment
Why is the requirement for distance measurement so important? Is it it only important for World Records?
I don't like that the rule is writtten as such that it is valid for all road competitions. There are small conventions which cannot follow strict rules for distance measurement.
If it is only for the purpose of World Records I would move the regulation to World Record guidelines and make a regulation that require IUF Sanctioned (Unicon) and Endorsed events to follow the WR guidelines.
Current regulation states that a free distance race must be 3% different from fixed distance race, and that the accuracy of distance measurement should be 3%. In theory, when measured more precised, it may happen that the course length fits in the fixed distance category.
Comment
> Why is the requirement for distance measurement so important? Is it it only important for World Records?
Distance measurement is extremely important for all competitions, because it makes no sense to advertise a race over a fixed distance if there is no guarantee that the race distance is at least the distance advertised.
Participants in competitions expect the results of different competitions - especially in fixed distance races - to be comparable. If a 10 km race is only 9.5 km long at some competitions, then there is no comparability. I think the measurement of the race distance is therefore one of the most decisive steps for all competitions.
Comment
For the comparatibility reasons, the race conditions, including a course disign are often of greater factor than distance measurement. As for a great example, the average speeds at Unicons where often greater at 42k than at 10k. I wouldn't be stating that the course measurement accuracy is extremely important, if there are other factors of greater importance.
Small conventions which cannot meet the requirements for distance measurement would have to abandon IUF rulebook. I would still prefere that the competition on such events are ruled by the IUF rulebook even though distance may not be as accurate. I would therefore make the rule applying only to certain type of competitions.
Comment
> As for a great example, the average speeds at Unicons where often greater at 42k than at 10k.
That may be, but it is also a comparison of different disciplines.
If I as an athlete want to compare e.g. 10 km with 10 km, but there is no guarantee that the 10 km were really 10 km, then the whole comparison is simply nonsense. For me as an athlete, the time at the end is meaningless if the distance is not guaranteed. Then we can forget about fixed distance races altogether and everyone can just run a distance that is as long as they want.
> Small conventions which cannot meet the requirements for distance measurement would have to abandon IUF rulebook.
Why? That's nonsense - you can't offer an e.g. official IUF 10 km race, but you can offer a road race that otherwise follows all the rules of the IUF Rulebook. Just not a race that corresponds to the official 10 km competition discipline - because for this it must be ensured that the competition distance is actually 10 km. And if this is not guaranteed, then it should not be an official 10 km race. I don't see the problem.
Comment
This proposal only concerns the measurement of fixed-distance races.
For free distance races, I suggest to delete the section “3D.15.3 Distance Measurement for Free Distance Races”. For me, the issue is not to measure the course of a free distance race, but rather to inform participants about the course (start and finish area, roads taken, direction, number of laps, etc.). If you know the course, it's easy to calculate the distance with any tool (without having to go there).
The measurement method described here requires more time and skill than money. Almost all track and field road races in the world are measured using the Jones counter method, which is universal. This method can be used for a neighbourhood race or for the Olympic Games (the difference will be in the experience of the measurers).
The method could be further simplified if we knew the databases that list calibration bases (athletics federations keep up-to-date databases).
That said, if it's too much of a burden to measure the course, I think that's an element in favor of organizing a free distance race.
Comment
> For free distance races, I suggest to delete the section “3D.15.3 Distance Measurement for Free Distance Races”. For me, the issue is not to measure the course of a free distance race, but rather to inform participants about the course (start and finish area, roads taken, direction, number of laps, etc.). If you know the course, it's easy to calculate the distance with any tool (without having to go there).
I would agree with that. A free distance race is less about covering a specific distance, which is why in my opinion a rather imprecise specification of the distance should be sufficient. The focus when selecting the course should be less on covering a specific distance and more on allowing an interesting race and offering a varied course, e.g. in terms of the elevation profile or similar.
> That said, if it's too much of a burden to measure the course, I think that's an element in favor of organizing a free distance race.
I completely agree with you.