Course length ratios, what to use?

[Paul Frost]

I'm confused.
Whilst controlling a level C event I have been using the tables in the Event Guidelines B: Long distance Cross Country Events
In which it gives the ratio of 0.56 for a blue course (with M16, M45, M50, M55 & M60 as the suggested age classes).
But...
Appendix B Course Planning, section 4, Running Speed ratios has the following:
M16 0.84
M45 0.86
M50 0.82
M55 0.77
M60 0.70
Mid 0.80

There is a massive difference between 0.56 and 0.80 (about 2.8k in this case)
It's too late now for me to change it for this event as the maps are now ordered, but for future reference what's the "official" answer?

If you want to test the calculations in the real world, come along to Loch Vaa, part of the Highland Wolf weekend 19/20th October.

[NeilC]

It depends how long you want the competitors to take. If you want the M21 runners to run their course in 70 minutes but the M50s to be out for 55 mins then the 0.56 may work. If you want them to be out for the same length of time then use the 0.8.

[GML]

It depends how long you want the competitors to take. If you want the M21 runners to run their course in 70 minutes but the M50s to be out for 55 mins then the 0.56 may work. If you want them to be out for the same length of time then use the 0.8.

But it isn't a Blue course if the course length ratio is 0.8 and the EWT is 70 minutes, it is a slightly short Brown course.

(According to Event Guideline B, what defines the colour of a course is the course length ratio and technical difficulty. I can't see anything in Event Guideline B that says, or even implies, that EWTs should be the same for all courses).

[Homer]

I'm confused.
Whilst controlling a level C event I have been using the tables in the Event Guidelines B: Long distance Cross Country Events
In which it gives the ratio of 0.56 for a blue course (with M16, M45, M50, M55 & M60 as the suggested age classes).
But...
Appendix B Course Planning, section 4, Running Speed ratios has the following:
M16 0.84
M45 0.86
M50 0.82
M55 0.77
M60 0.70
Mid 0.80

There is a massive difference between 0.56 and 0.80 (about 2.8k in this case)
It's too late now for me to change it for this event as the maps are now ordered, but for future reference what's the "official" answer?

If you want to test the calculations in the real world, come along to Loch Vaa, part of the Highland Wolf weekend 19/20th October.

As NeilC points out, it's the difference between running speed ratios and course length ratios. Those running the Blue want to be out for a shorter time than those on Black and are also running slower, hence the difference.

Furthermore, Guideline B doesn't have M45 and M50 on Blue; they should be doing the Short Brown.

[Paul Frost]

Furthermore, Guideline B doesn't have M45 and M50 on Blue; they should be doing the Short Brown.

Not for level C event, it's Blue.

I can see how/where I would apply the course length ratio (to the length in kilometres of black).
The only reference to a winning time I could find was that M21L should be 67mins.
There is no mention of winning times for any other age class or course colour

Event Guideline B : Long Distance Events
3.6 Notes: (a) The Black course, if planned, would equate to the M21L course at an old style Regional Event, with an expected elite winning time of 67 minutes. All other course lengths should be scaled to the length required for this course, which has been allocated a course length ratio of 1.00.
Where no Black course is planned, it is still necessary to determine the length of a nominal Black course with an elite winning time of 67 minutes in order to use the ratios for the other courses. In this instance the winning time on the Brown course by a top standard elite competitor should be 57 minutes.

So on the 0.56 calculation the Blue should be about 38mins.
But the 0.80 mid point of the age classes listed in the the course planning document would give about 54mins.

For a less experienced controller these ambiguities are very confusing. Surely there should be some "official" view on the expected winning times for each course / class. Having two sets of ratios that produce very different end results is not helpful, either to controllers or competitors.

[King Penguin]

I agree 2 sets of seemingly incompatible guidelines are not helpful - even more so when most events don't have the mythical Black course on which everything is to be based, and if they do it's usually inquorate !

[NeilC]

I agree 2 sets of seemingly incompatible guidelines are not helpful - even more so when most events don't have the mythical Black course on which everything is to be based, and if they do it's usually inquorate !

Don't worry there will only be one next year (I've just finished editing it). It still won't give an EWT for a blue course though, that depends much too much on who turns up.

In contrast for age class events where the quality of the field is more predictable we do have EWTs quoted
http://www.britishorienteering.org.uk/i ... A_2013.pdf

[graeme]

Sadly, none of this has been remotely thought through. Normal people please skip the next paragraph.


Once upon a time the course lengths were all sensibly set up in terms of "winning time for an elite man". This automatically dealt with issues like SOL6 where the terrain was very different in different parts of the area. Unfortunately this was thought to be a bad thing because there were few elites on green. Some careful research revealed that in "typical" terrain (read - nice southern forests) speed ratios for various classes were well observed. Now armed with these, age class distances for badge event were calculated in terms of winning time for M21, desired winning times for M/Wxx. This is actually more convenient if you have a homogeneous southern forest. Then when the move to colour coded came in there was an attempt to simplify back to an evenly spaced set of course lengths, defined by time taken (still reading? really?) but this then got transformed back to the homogeneousness assumption-hypothesis based on relative velocities (look, I'm now using long words, did you get the message yet?). Further transmogrification to a chronologically-based competition classification ensued, subsequently enshrined in guideline B as previously reported (no? really? you understood that first time through?).


It's Loch Vaa FFS, you can get great courses by chucking darts at the map.

[NeilC]

2.6.3 Applying the course length ratios – points to watch out for:
• M21 (or Black) probably uses the whole area. The shorter courses use only part of it, and this might be more or less runnable, or steeper/flatter, than the average
• rough terrain has a greater effect on the running speed of younger and older competitors than of M21s
• older competitors are significantly affected by steep terrain, particularly downhill
• older competitors find dense tree growth more of an obstacle – suppleness decreases with age
• There is no magic formula for allowing for these variables (though no doubt Graeme or Murray (http://murraystraining.blogspot.co.uk/) could have a good stab at one)

[Homer]

It's Loch Vaa FFS, you can get great courses by chucking darts at the map.

Yes, agreed and I'm sure it'll be one of the best races of the Autumn whatever..
The 6.5km looks about right for a M21E Middle Distance so a 35min winning time, depending on who turns up. Not sure it's been billed as Middle Dist though

[greywolf]

I thought controllers were supposed to understand this stuff

The simple version is:
Black course - planned to be won by a top elite in 67 minutes
If no Black course then Brown course planned to be won by a top elite in 57 mins
Green course should be just under half the Brown course length (corrected for height)
Blue course should be a bit closer (course length correctd for height) to Green than Brown

Obviously it's fairly important that planners/controllers know how fast the elite can run....

[Paul Frost]

It's Loch Vaa FFS, you can get great courses by chucking darts at the map.

Well the planner seems to have carefully thrown the darts in quite a systematic way, so hopefully that will still result in courses that meet peoples expectation.

Yes, agreed and I'm sure it'll be one of the best races of the Autumn whatever..
The 6.5km looks about right for a M21E Middle Distance so a 35min winning time, depending on who turns up. Not sure it's been billed as Middle Dist though

It's not advertised as, or been planned as, a Middle Distance. It's part of a whole weekend of events, so more of a warm up for the Sprint race in the afternoon and the main (level B) Scottish O League event on the Sunday at Inshriach. The limited range of courses is due to the pressures on a small club putting on 3 events in 2 days and a ceilidh and how many SI units and stakes that we could lay our hands on.

In contrast for age class events where the quality of the field is more predictable we do have EWTs quoted
http://www.britishorienteering.org.uk/i ... A_2013.pdf

That's just for the British Long Distance Champs though, not all age class events. I'm sure the Scottish 6 Days will not be using those EWT's.

[Paul Frost]

I thought controllers were supposed to understand this stuff

I might just as well have asked "how long is a piece of string" for all the differing answers I've been given by assorted experienced controllers.
It's no wonder there are so many debates and complaints about course lengths and winning times

I'm reminded of a thread I started in Jan 2012 "Are old men getting too quick" which makes interesting reading 22 months on.

[pete.owens]

I thought controllers were supposed to understand this stuff

I might just as well have asked "how long is a piece of string" for all the differing answers I've been given by assorted experienced controllers.
It's no wonder there are so many debates and complaints about course lengths and winning times

I really don't see the confusion - the guidelines are pretty straightforward and unambiguous. All the people contributing here (at least those answering seriously) have given you pretty much the same answer - if worded slightly differently.

The length (adjusted for climb) of a blue course (and all other courses) is defined as a ratio (0.56) of a nominal black course run over the same terrain. The only running speed that comes into the calculation is that of a nominal elite runner who would win the nominal black course in 67 minutes.

The association with age classes are only suggestions as to which classes to assign to which to which courses IF you were running an age class competition at events with different selections of courses. In any case the table you quoted in the original post was for a typical event with a choice of 4 technical courses, rather than the 2 at your event. Your blue course would be catering for M16-M21-M60 + W18-W21-W45 if it was an age class competition - and to attempt to plan a course to give a winning time for such a wide range of classes would be pointless.

[graeme]

It still won't give an EWT for a blue course though, that depends much too much on who turns up.

...and basing it on the time taken by someone who didn't turn up on a course that doesn't exist is simpler because ... ?