Did you even watch the video?
Did you even watch the video?
You obviously don't know how GPS watches work.
Obviously a history major. Rojo's math is wrong. The times he calculated are off by a order of magnitude and would require the track to be short by 1.5 meters per 100 meters. I think that would be noticeable.
I noticed that Molly Huddle was wearing a watch in the 10k. I'm not sure if it was GPS or if she was running with it off (Mike Rossi style). Anyhow, it'd be interesting if her watch recorded less than 10k (probably not though with her swinging wide in the final stretch to let Emily by). Anyhow, if her watch recorded less than 10k, this would prove that the track was short (or her watch is inaccurate).
I once paced a half marathon group, and told everyone that we'd have to run about 4 seconds faster per mile, because we could not bee-line the entire course, and that our GPS watches would show that we ram further then 13.1 miles. At the end of the race, my watch showed that I ran 12.99 miles. Others showed that they ran 13.00 miles. I could not find anyone who ran 13.1 miles or further. At that point we concluded that the course was short (or that I took everyone on a shortcut).
Pacer again:
Was your race under significant tree coverage? What you described I have seen on certified courses under tree coverage. If you have any turns under coverage, GPS may not see
Tree coveri wrote:
Pacer again:
Was your race under significant tree coverage? What you described I have seen on certified courses under tree coverage. If you have any turns under coverage, GPS may not see
The race was along a waterfront of a large city and had very little tree coverage. The pace we were running and what our watches were showing seemed right up until mile 12. I think someone measured the course for 13 miles rather than 13.1. It wasn't the best weather conditions, but just about everyone in my pace group and other pacer's groups ran a PR. I'm pretty sure the course was just short.
I recently did 170 laps around the CU track in a Relay for Life wearing my Garmin (I know this is nuts; so no need to tell me I'm crazy). This works out to about 42.25 miles but the Garmin only thought I went 39.87 miles. I also measure and certify road races (Bolder Boulder is one I have measured) and know from experience that road course seldom measure on the Garmin what the Jones Counter says the distance is. Tracks...Garmins usual under measure; road race...Garmins usual over measure.
Pacer Again wrote:
I noticed that Molly Huddle was wearing a watch in the 10k. I'm not sure if it was GPS or if she was running with it off (Mike Rossi style). Anyhow, it'd be interesting if her watch recorded less than 10k (probably not though with her swinging wide in the final stretch to let Emily by). Anyhow, if her watch recorded less than 10k, this would prove that the track was short (or her watch is inaccurate).
I once paced a half marathon group, and told everyone that we'd have to run about 4 seconds faster per mile, because we could not bee-line the entire course, and that our GPS watches would show that we ram further then 13.1 miles. At the end of the race, my watch showed that I ran 12.99 miles. Others showed that they ran 13.00 miles. I could not find anyone who ran 13.1 miles or further. At that point we concluded that the course was short (or that I took everyone on a shortcut).
[quote]Benji Durden wrote:
I recently did 170 laps around the CU track in a Relay for Life wearing my Garmin (I know this is nuts; so no need to tell me I'm crazy). This works out to about 42.25 miles but the Garmin only thought I went 39.87 miles. I also measure and certify road races (Bolder Boulder is one I have measured) and know from experience that road course seldom measure on the Garmin what the Jones Counter says the distance is. Tracks...Garmins usual under measure; road race...Garmins usual over measure.
[quote]
I gave up on using a Garmin on the track. Even the map it creates shows i was all over the track, even if I stayed in Lane 1.
For road races, I've noticed my Garmin consistently records about 13.25 miles for halfs, and 26.5 for fulls. I always figured the extra distance was due to running the turns wide due to the crowds, or zig-zagging across the road to get to water stations, or similar problems in running straight tangents between the inside corner of each turn. The half race I mentioned where i recorded 12.99 miles was the only time I recorded less than 13.15 for a half. I think the RD either made a mistake, or intentionally under measured the course short to get participants pumped about running a PR and have them spread the word that the race had a fast course. This wasn't a race with prize money or elites, so I don't think anyone was worried about any records being invalidated.
This explains why Ayana crushed Dibaba. She was running on a shorter track.
I was using the Garmin as a lap counter and a soft check of my pace to keep me aware of what I was doing since I was in unknown territory after the marathon distance. I didn't think it would give me a good measure of the distance. It was interesting to see how far off it was at the end of the 170 laps.
Pacer Again wrote:
[quote]Benji Durden wrote:
I recently did 170 laps around the CU track in a Relay for Life wearing my Garmin (I know this is nuts; so no need to tell me I'm crazy). This works out to about 42.25 miles but the Garmin only thought I went 39.87 miles. I also measure and certify road races (Bolder Boulder is one I have measured) and know from experience that road course seldom measure on the Garmin what the Jones Counter says the distance is. Tracks...Garmins usual under measure; road race...Garmins usual over measure.
[quote]
I gave up on using a Garmin on the track. Even the map it creates shows i was all over the track, even if I stayed in Lane 1.
For road races, I've noticed my Garmin consistently records about 13.25 miles for halfs, and 26.5 for fulls. I always figured the extra distance was due to running the turns wide due to the crowds, or zig-zagging across the road to get to water stations, or similar problems in running straight tangents between the inside corner of each turn. The half race I mentioned where i recorded 12.99 miles was the only time I recorded less than 13.15 for a half. I think the RD either made a mistake, or intentionally under measured the course short to get participants pumped about running a PR and have them spread the word that the race had a fast course. This wasn't a race with prize money or elites, so I don't think anyone was worried about any records being invalidated.
I have a Garmin GPS mounted on the handle bar of my bike when I measure courses for certification. Since the Jones Counter is mounted on the axle, the GPS is a good tool to alert me when I should slow down to look at the counter. 99% of the time, the GPS will give me a reading of 1.0-1.01 for each mile ( I always re-set the GPS to zero at each mile). The only time I got a reading of less the 1.0 was due to signal blockage due to buildings or trees.
The shortest distance between two points is a straight line. So if the sampling frequency of the garmin is even a little slow then it should under estimate distances around a track.
Road races a different beast since most courses are measured by tangents and it is impossible to run perfect tangents in a crowd.
Rapper's Delight wrote:
This explains why Ayana crushed Dibaba. She was running on a shorter track.
This is so very wrong. The shorter the distance run, the more it would favor Dibaba. Not only would Dibaba have been tired, so the shorter she runs the better for her, but also Dibaba's body is better designed for the 1500m than the 5000m, so she would also benefit from a a shorter track for that reason as well. However, all that aside, the difference between the distance run on a shorter track and the distance run on an accurate track is so miniscule compared to the total distance run that it wouldn't affect the endurance of the athletes anyway. So yeah, you're tripley wrong.
D.Katz wrote:
I started reading this thread and couldn't stop laughing. Some of you have way too much time on your hands.
I was in Beijing (returned on Friday due to other obligations) and can attest that the track is accurate. Yes, people were joking that it was short - something that always happens when you have fast times. For the most part the conditions were excellent for the sprinters and horizontal jumpers. The Mondo surface was new and even Claye mentioned that it was very fast.
IAAF Certified Tracks are measured with EDM's and verified by independent surveyors. While there is no guarantee that mistakes can't happen, there are simple ways to check for the accuracy of many of the marks.
The Bird's Nest track is a standard IAAF track with a radius of 36.5m. Knowing this it would be easy to measure the diameter (finish line straight across to the 800m breakline - assuming the finish is on the tangent - which it is.
Then all you would need to do is measure from the break line to the 200m start. You could also measure from the finish line back to the breakline (point) for the 5000m. This would give you all the information you would need to calculate the distance of one lap in lane 1.
The 400m starts would have to be correct otherwise the runners would be crashing into the hurdles, same for the 110's and 100h.
The first day I arrived and did a walk around the track and all the marks seemed to be in the correct positions. I realize this is very inaccurate but there are several marks that must be oriented near each other - for example: the 400m hurdle marks must be in the same exact position as the beginning of the lat 4 x 100 exchange zone.
I also assisted with a measurement of the start of the walks which was just past the last hurdle of the 110. That measurement verified the placement of the last hurdle which confirms all the others.
David Katz
You only offered anecdotal evidence. Walking around the track and noticing that things seemed to be in the right place doesn't tell us anything about the length of the track.
If we're going to take this seriously then someone needs to measure it, either with a steel tape or surveying equipment. And forget about measuring the turns 10 cm out from the rail with a tape. That's too inaccurate. Measure the radius of the turns and the length of the straights. Some effort needs to be put in to make sure the turns are proper half circles. Measure a few "cords" on the turns and make sure they match and you're done. Two people could do this in 15 minutes.
In high school we ran a State qualifying meet on a new track that had all it's staggers in the wrong places. What a mess that was!
It's probably right, but I sure would like to hear that the brojos measured it themselves. It would be a great story if the track came up short. Stranger things have happened in sports. Big scoop for the brojos. It's worth the effort.
What you are asking for has already been done by independent surveyors and the report is on file with the IAAF. This is an absolute requirement for a IAAF Class 1 Certification. This also includes the levels of the track, runways and all landing areas. In addition, core samples of the track are taken and tested.
David Katz
IAAF Technical Committee
Member, Editorial Board of the IAAF Facilities Manual
fyi - measurements are taken 30cm from the curb not 10 cm
Ayana discover secret!
Run on shorter track than Dibaba!
This why Ayana win race!
D.Katz wrote:
What you are asking for has already been done by independent surveyors and the report is on file with the IAAF. This is an absolute requirement for a IAAF Class 1 Certification. This also includes the levels of the track, runways and all landing areas. In addition, core samples of the track are taken and tested.
David Katz
IAAF Technical Committee
Member, Editorial Board of the IAAF Facilities Manual
fyi - measurements are taken 30cm from the curb not 10 cm
Please don't try to pull rank on me by flashing your credentials on a web site populated entirely by trolls, and in a thread where we're discussing the possibility that a track which hosted an Olympics and a World Championship might be short by 1.5 meters. This thread is a farce and you're ruining the whole spirit of the thing by pretending to know more than we do.
Besides neither YOU nor your credentials actually measured the track did you? We all know someone with credentials and fancy equipment built the track to tight specifications... but none of us checked it personally, not you, not me, none of these nice trolls who spend their time sharing conspiracy theories with us.
And THAT is precisely how big mistakes get made, when everyone from top to bottom assumes some expert has already checked it.
You have a great day :)
D.Katz wrote:
You have a great day :)
That's it. Run away when challenged. Turn a blind eye to the obvious chicanery going in Beijing.
It's already been well established in the Mo Farah thread that lanes which should have been 1.22 meters wide were only 1.22 centimeters wide! And that the hypotenuse of a right triangle with sides of 50 meters and 8.75 centimeters was measured to be 80 meters! We all saw it!
Then Dibaba sets an 800 meter world record at the end of a race while doing cartwheels. Then Eaton runs a 45.00 where even HE demands that they check the equipment or the clocks or the breakfast tea. He knows something is off. Oh yes. He most surely knows.
This smells fishy. Something sinister is afoot. Something is rotten in Denmark. The lid is off this bag. The cat is out of the ... whatever.
Even you can see from your ivory tower that the Chinese have found a way to distort the very rules of Euclidean Geometry. If those with credentials refuse to get to the bottom of this, then it is down to the lesser folk to do the heavy lifting as usual.
I don't know how you sleep at night. Have a nice day? Indeed!
You disgust me.
D.Katz wrote:
What you are asking for has already been done by independent surveyors and the report is on file with the IAAF. This is an absolute requirement for a IAAF Class 1 Certification. This also includes the levels of the track, runways and all landing areas. In addition, core samples of the track are taken and tested.
David Katz
IAAF Technical Committee
Member, Editorial Board of the IAAF Facilities Manual
fyi - measurements are taken 30cm from the curb not 10 cm
Which is why you can run a little shorter than 10k in a track 10,000 if you run closer to the curb than 30cm. 15cm is quite possible.