Skip to main content

8 replies

Ironman Kona run course length

K kcb203Member
There's an interesting discussion going on at slowtwitch.com about the length of the Ironman run course in Hawaii. The course was USATF certified in 2003, but I deduced that the course was not run this year as it was certified (or any year since 2004 or 2005 based on GPS turnaround points recorded by users at Garmin Connect).

I raced the Ironman World Championship for the first (and likely the last) time this year. The 2003 certification is the most recent certification for the course, but the start has changed since 2003 and the turnaround locations were not placed in the same locations as the 2003 map.

Based on conjecture on slowtwitch.com website that the course was short, I looked at my GPS track to identify the start, finish, and turnaround points and compare them to the points certified in 2003. (I did not just look at my overall GPS track length, which I know is not accurate compared to a properly certified course with a Jones counter.)

I identified three variations from the certified course. The biggest discrepancy is #3, below. Otherwise, we ran the same certified route:

1) Starting route

The start in 2003 was in the parking lot behind the King Kamehameha hotel, and now it is at the foot of the pier next to Ali’i Drive .

It is clear that the start has changed. I estimated the change by using the path function in Google Earth and measured the course we ran in 2011 compared to what was certified.

Pictures of my rough measurements are here:

http://forum.slowtwitch.com/cg...post=3594368#3594368

I estimated that we ran 489’ feet less in 2011 than the 2003 certification. I looked at historical satellite images in Google Earth, and I don’t think the configuration of the tennis courts, parking lot, or roads has changed since 2003.

2) Ali’i Drive Turnaround

The first turnaround on the map is listed as 16’10” south (or past) the “No Parking” sign at St. Peter’s church. If the sign is in the same location now as it was in 2003, the sign is located just north of the sidewalk to the church. You can actually see the sign here:

http://maps.google.com/maps?q=...bp=12,186.61,,0,1.82

We ran about 175’ past the church before turning around for a total of 316’ extra feet ((175’-16’10”) x 2). You can see my Google Earth measurement based on my GPS track here.

http://forum.slowtwitch.com/cg...post=3593299#3593299

I’m aware that the turnaround point on my track could be off by ~30’, but there is still somewhere between 256’ and 376’ of extra distance over the certified course.

3) Energy Lab Turnaround

The second turnaround is listed as 295’10” north (i.e., past) the gate to the West Hawaii Explorations Academy . Based on my Garmin file, we turned around 902’ before the school (i.e., south) for a total of 2396’ short ((296’ + 902’) x 2).

Here’s the picture of my GPS track and my measurement to the WHEA driveway, which is right in front of the gate that I presume is the same gate that was identified in the 2003 map:

http://forum.slowtwitch.com/cg...post=3593299#3593299

Again, I realize this could be off 30’ or so either way, but it’s still well over 1000’ short (multipled by two because we ran out and back).

To add this up:

138,435’ in a 42,195 meter marathon (leaving out the .1% SCPF)
-489’ shorter in 2011 at the start than the 2003 certification
+316’ extra distance in 2011 at the Ali’i Drive turnaround
- 2396’ short in 2011 at the Energy Lab turnaround
= 135,866’ in the marathon = 25.73 miles = .486 miles short (it's .51 miles short if you consider a marathon to be 42,195m x 1.001 with the SCPF)

Everybody’s Garmin shows the course somewhere just under 26 miles. I know that Garmin measurements shouldn’t be compared to a Jones counter measurement, but on the flip side, it’s the only certified marathon I’ve ever seen where everyone’s GPS is consistently short rather than .2 to .4 long. This backs up my theory that the course is short. And the conditions for GPS are pretty good out in the lava fields with no obstructions.

Any thoughts on this? It seems that if a local 5k goes to the trouble of certifying the course, the Ironman World Championship should do so as well. The course has changed significantly since the move to Kona in 1982, and the course record was broken this year by 8 seconds. Query what it means to break a course record by 8 seconds on a course that is different and likely .5 miles short, though who knows the length of the course from 1996 when the men's record was set. The women's run record was set this year, but according to the GPS tracks I pulled off Garmin Connect, the turnaround points have been in the same--albeit incorrect--place since 2005 or so.
Original Post

Replies sorted oldest to newest

M mikesandfordMember
kcb203:

I should think that you will find a lot of sympathy amongst the road race measurers here over your frustration with the inaccuracy of the running leg of triathlon courses.

I think your method of investigating the distance, which you ran in the Iron Man champs in Hawaii, is very sound. I have used very similar techniques in tracking down cases of certified road races in England where the race director has changed the course from that originally measured without informing his paying customers, or indeed the certifying authority.

The triathlon governing body in UK has no "proper" rules or standards for measurement and certification of distance. They just say distances must be accurate without defining how accurate. When we (the Association of UK Course Measurers) asked them if they wanted a course measurement and certification service, they were not interested.

We have also had a lot of trouble over here with companies who most of the year organise triathlons and biathlons, but then in the late winter, when it is too cold for swimming, organise road runs and hoodwink runners by claiming accurately measured courses. Sometimes they ask us to measure and certify. But while they may find a measurer to measure, they wont get it certified as accurate since we only certify road races licensed by one of our road race governing bodies, UK Athletics, or the Association of Running Clubs. These bodies have "proper" rules for the conduct of road races and for their measurement.

Good luck with your campaign to spread greater awareness amongst the triathlon community of the lack of precision and also unreliability of the race length claims by organisers of triathlons. I would be interest to hear if you make any progress with the various governing bodies for triathlon.
duanerussellduanerussellMeasurer
In the last month, I was reading another bulletin board that was having this same discussion. If I had time to look for it I would, but I am short of time right now.

But, there were a couple posters who claim to be inside the triathlon governing body, and they claim that the rules state that a distance must only be within 10% of the claimed distance. They acknowledged that a "marathon" course in a triathlon could be 38km (instead of 42.195 km) and still be considered valid.

To us in the running community, that is misleading. But, those are apparently the rules, as the triathlon community apparently feels they are competing against other people, not the clock. Thus, the organizers don't see a need for accuracy in course length.

Just sharing what I read recently.
peteriegelpeteriegelRCMBB Founder
TRIATHLON MEASUREMENT

Measurement of a triathlon presents difficulties that we don’t encounter in road course measurement.

Let’s begin with the length of a triathlon. As I recall, the early Ironman was nominally a 1.5 km swim, followed by a 100 mile bike ride, followed by a marathon run. Let’s use this as an example.

The first job is to find available areas for start, finish and transition areas. Start and finish will probably be required to be in areas where parking or bus transportation are available. The start will be on a beach somewhere. The layout of the swim can be done simply. Just pick some spots on the beach, and lay out some buoys in the water around which the swimmers must pass. The only practical way to do this is to set up some electronic distance meters on the beach and put people, radios and buoys in boats. Trial-and-error triangulation, and moving the boats around, can be used until the buoy locations are established. Now we have a 1500 meter course.

Once the swimmers finish, they must run from the swim finish to the bike start, picking up their bike shoes enroute and finding their bikes. Then they begin their bike ride. Question: Does the transition area figure in to the course length? Which portion? In any case, the start of the bike ride must be established, and a measurement of a 100 mile bike course will be needed. Barring a miracle, the end of the bike ride will not fall in a convenient spot with a decent transition area. What’s to be done to adjust it? If it was a run, a turnaround could be used to make it come out right, but biking around a TA point is undesirable.

Then another transition takes place for the final marathon run, and again the question arises as to whether the bike finish to the marathon start counts as part of the overall distance.

With a suitable marathon start established, the run can be measured. Again, the length will likely not fit exactly with the desired Ironman finish location. Here a TA could be used.

I would hate to have the job of measuring the entire course. It involves use of surveying equipment and over 250 miles of bike riding, as well as requiring several adjustments to the course as the various transition locations are found to need adjustment.

I can’t say I’d relish the measurement job. It would be hugely expensive and time-consuming, and might well be found to be impossible given the need to find nicely-placed transition locations. Adjustments would certainly be needed, and given the need for standard lengths and available transition locations, would add time and complexity to the job.

The situation could be eased, as the triathlon folks have done, by allowing the various course lengths to vary somewhat from the standard distances. Then measurement would be straightforward and uncomplicated. But what would we then have? The distances would not be standard, and a records system would need to account for the differences in course lengths.

I think the triathlon folks have done as well as is practical. The Ironman venues do not lend themselves to fitting the pieces into standard-distance lengths.
Last edited by peteriegel
AdminAdminMember
I can understand the difficulties with trying to find suitable venues that result in courses that turn out to be standardized distances, and also the difficulty, and expense, of accurately measuring such long courses.

But I can't understand why the already-laid-out courses can't be measured with Google Earth and those approximate distances be advertised. Advertising the run as a marathon when it takes only a few minutes on Google Earth to determine it is well short of a marathon is not right in my view.
D davidkatzMember
I don't understand why the tri folks don't incorporate the standards for the 3 sports.
I may be in a little different situation then most of the other measurers - I often serve as the technical director. Producing an accurate run segment of a tri is the easy part. Sure, there are always challenges to make an accurate course but we (they) owe it to the participants.
K kcb203Member
Thanks for the feedback everyone. I'm glad that nobody found a glaring flaw in my methodology. I've become satisfied that if the 2003 course is correct, the race as run this year is short.

I see no reason why a major triathlon should have a less accurate run course than a USATF certified running race.

The swim is tougher. At least it was before handheld GPS and Google Earth. It is probably difficult and expensive to get an exact swim course measurement. But I don't think triathletes expect that. But with the advent of Google Earth and handheld GPS, it's a simple matter to plot the course, record the turn points, then drop a buoy at those spots. Of course, buoys can drift, GPS isn't exactly accurate, and Google Earth may not exactly line up with the depicted coordinates. But it should be possible to be within 50m or so, which is 40 seconds to a minute for most swimmers. Swim courses are routinely off by much more than that. Legend has it that the US Navy once laid out an Ironman swim course and made it 2.4 nautical miles instead of 2.4 statutory miles.

Bike: I think expectations on the bike are lower. It can't (or shouldn't be done) based on USAFT standards because in triathlon, we're supposed to ride on the right side of the road, so the shortest possible course standards wouldn't apply. But there's no reason the general principles couldn't be followed with a calibration course, etc. Even this is too much, though. I don't think most triathletes would object to the use of Mapmyride or a GPS to plot the bike course. And most people prefer an interesting course to exactitude. For example, the Ironman Wisconsin course is lollipop shaped, and the typical route from the lake to the loop part was under construction this year. The alternate route was a mile or so longer, but there was no real alternative without totally redoing the course. There aren't any out-and-backs to massage the distance, and the start/finish are fixed by the transition locations.

Run: I think it's a given that we often run more than the distance when the transitions are counted. For example, at Lake Placid, it's about .25 miles from the lake to where the bikes are racked. But there's no way to avoid that. At Kona, all athletes run a loop around the entire pier in both transitions. I've heard reports that when this is added to the run course, the total is 26.2. Most transitions are laid out so that everyone runs the same distrance regardless of where their bikes are racked. The run course should be the exact certified distance and start at the timing mats at the exit from T2 and end at the finish line.
duanerussellduanerussellMeasurer
kcb203, I agree with most of your assessment. Swim leg is inexact, but expected. For the Bike leg, though, SPR can include the lane restrictions you mentioned. Measuring with a Jones counter, though, could be problematic on a 100 mile course. A GPS or MapMyRide would be close enough.

The transitions shouldn't be counted in the overall distance, as there usually is congestion there, and no one wants to be slowed on a timed portion (although most Tris do show your transition times). Run courses could be USATF-certified.

The issue I see, though, is when a Tri advertises a Marathon or Half-marathon leg, and those are only within the 10% tolerance. They should not be called "Marathon" length, if they are not. If you don't want to accurately measure the leg, then call it "about 26 miles" for the run. Specific distance claims have expectations of accuracy. Tris should not advertise a distance as specific, unless they measure it properly, or if they state somewhere near the distance claim that it has not been accurately measured. But then, most of us are Type-A folks, so accuracy in statements matters. Maybe many participants aren't as concerned. Smiler
michaelbowenmichaelbowenMember
Hey, Duane - I was going to comment about being the guy you referred to as inside the USAT, but I've never found anything in my (R.D.) manuals which allowed for a 10% shortage. (We were told in our certification course to make certain the run course was as accurate as possible.)

It's a shame that WTC (a company whose standards are outside those of ITU or any national governing bodies) can't ensure a run course is accurate to the standard/s by which we hold our work.

Add Reply

Post

Membership Required

We're sorry. You must be signed in to continue. Sign In or Register
×
Are you sure you want to remove from your Block List?
×
Loading...
×
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .
×
Link copied to your clipboard.
×