malmo wrote:
interested reader wrote:
The OP measured the "diameter" of the track. Guffaw
Katz made the best post, imo.
He should. He's the only known expert on track (and road) certification who has ever posted on LRC.
Yes I know, hence my comment.
malmo wrote:
interested reader wrote:
The OP measured the "diameter" of the track. Guffaw
Katz made the best post, imo.
He should. He's the only known expert on track (and road) certification who has ever posted on LRC.
Yes I know, hence my comment.
Don't forget that Bekele also had to deal with wind resistance in the open stadium in Hengelo as well as run longer. He didn't have fancy laser beams, the world's bounciest surface to run on, no proper pacing and cheaterfly's. I heard somewhere here that Bekele's WRs were not even at his potential as he had some sickness leading up to them(could be the 10,000m). Renato said so. Now throw 2004 Bekele into Monaco last week and we would literally be looking at a 5,000m all run at sub 4 minute mile pace. This is all not considering the fact that anything dirty was going on in Monaco.
While I agree that some of the "analysis" posted in this thread is nonsense, the overall premise raised by the OP is fair. I don't know of anyone who has run a race on a track and not have had their Garmin measure longer than the distance. NYRR has been having a bunch of virtual races since Covid began and if you look at the activities for people who ran them on a track, you'll notice that for a 5k, for example, most people hit 5000m on their Garmin close to 200m shy of actually running the full distance. For JC to be so close to 5000m on his device should be surprising. Does this mean that the track is short? No, but it's a fair observation to make.
I ran a 5000m in a similarly closed stadium and my watch only recorded 4200m. Apart from that, it's very precise and in open stadiums i get 5100-5200 every time.
Drop the nonsense, for it to be ratified, there has to be a track measurement again anyway as per official rules.
raw speed wrote:
I ran a 5000m in a similarly closed stadium and my watch only recorded 4200m. Apart from that, it's very precise and in open stadiums i get 5100-5200 every time.
Drop the nonsense, for it to be ratified, there has to be a track measurement again anyway as per official rules.
So in summary, you agree with me 100%. Thanks.
browski wrote:...I don't know of anyone who has run a race on a track and not have had their Garmin measure longer than the distance....
News flash... a hand-held (or wrist-strapped) GPS device is not an accurate instrument for measuring distance travelled along the ground. It gives you an approximation of distance travelled, with accuracy depending on a number of factors, including satellite coverage, rate of measuring, curvature along the travelled path...
I had a similar problem! I purchased a 10 acre lot but years later, after some serious digging on google maps, I found it was a few square feet over the advertised area. I’m not telling anybody but live in constant fear that I’ll be sued for a few more dollars.
Internetsherlock wrote:
forcerunner wrote:
LOL at trying to measure with google maps.
I believe google maps use the same scaling variables factors on all map locations . Also if you measure something today on the map , the distance wont change if you measure again next month or next year, no such thing as a GPS signal interference
Because it is a projection of the earth spheroid onto a flat map, a frame is slightly compressed in the center and stretched on the edge, so the scaling is not perfectly uniform. No idea how much difference this makes in practice.
rekrunner wrote:
malmo wrote:
I'm not sure how you came up with that conclusion?
If you have perfect measuring and perfect semicircles, then the track can be measured accurately.
What I meant was "assuming google was a perfect measuring device". With shorter straights and a larger semi-circle radius (see above for exact figures) we can still theoretically have 400m tracks with these shorter long-axis measurements.
The other main error I pointed out, is that the long-axis measurement performed by the OP for FBK does not go through the center of the track, but is slightly offset to the left (or right depending on which way the viewer is facing). Any accurate measurement not going through the origin of the semi-circles will be short.
I'm still not getting what you mean by "long axis measurement"? A semi-circle has a precise definition. A straight line has a precise defintion. If you have an accurate measuring device then the nominal and actual length of a track can be measured.
was on this track once, well, it is not for nothing that it is considered one of the best
rekrunner wrote:
Assuming your measurements are accurate (*), and assuming two straights and two semi-circles, and that both tracks have a curb, with a curb factor of 0.3m, then both tracks are short ("mathemetician" got that right).
A standard track will have straights of 84.39m and two semi-circles with radius 36.5m.
Therefore your long axis measurement should be 157.39m.
You measured 156.57m for FBK and 155.94m for Monaco.
I see a lot of math results in this thread, but none of it seems to add up, but maybe I made different assumptions.
Adding the curb factor of 0.3m to a standard track gives 400.001219m.
If the long axis is truly short we must determine if the radius is short, or the straight is short (or both). Still assuming a curb factor of 0.3m:
FBK:
Short straight: Straight=83.57, Radius=36.5, Long Axis=156.57, 1 lap=398.361, short by 1.639m
Short turn: Straight=84.39, Radius=36.09, Long Axis=156.57, 1 lap=397.425, short by 2.575m
Monaco:
Short straight: Straight=82.94, Radius=36.5, Long Axis=155.94, 1 lap=397.101, short by 2.899m
Short turn: Straight=84.39, Radius=35.775, Long Axis=155.94, 1 lap=395.446, short by 4.554m
(*) There are several reasons to doubt whether your google maps method is accurate. Even if we assume the maps are to correct scale, and no overlapping photo errors, there is the issue whether you clicked the right endpoints of your long axis, which must be both exactly at the inside curb, and at the mid-point of the curves, and the accuracy with which you can do that from an image on your computer with a mouse. Your FBK measurement is measurably off-center, closer to one straight, and it looks like you made the same error on the Monaco track. Furthermore, it looks like your Monaco endpoints don't quite reach the curb at each end. And obviously, if the track is not two straights with two semi-circles, then all bets are off.
But, as Citizen Runner pointed out, the cartographic projection is not truly representative of the actual dimensions of the track.
malmo wrote:
I'm still not getting what you mean by "long axis measurement"? A semi-circle has a precise definition. A straight line has a precise defintion. If you have an accurate measuring device then the nominal and actual length of a track can be measured.
In the first post, the OP told us he "decided to measure just the diameter" of the two tracks.
It is the white lines in the pictures.
Thinking "diameter" was the wrong term for a track shaped object, I called it the "long axis".
With this single measurement, even assuming it is infinitely accurate (and no other errors), we cannot yet conclude the track was short, because it does not give us the length of the radius nor the length of the straight.
That is all I'm saying.
Cartography basics wrote:
But, as Citizen Runner pointed out, the cartographic projection is not truly representative of the actual dimensions of the track.
This is not the only issue -- the mathematics are only valid assuming ideal conditions for the sake of discussion.
And those ideal conditions should include the Earth momentarily stops rotating so it doesn't contribute to the relative motion of the runners around the track. This isn't symmetric - the Coriolis effect constantly helps them out.
Ideally tracks should be centered on the equator to minimize this
https://www.youtube.com/watch?v=OnB4qMT5R_YBad Wigins wrote:
And those ideal conditions should include the Earth momentarily stops rotating so it doesn't contribute to the relative motion of the runners around the track. This isn't symmetric - the Coriolis effect constantly helps them out.
Ideally tracks should be centered on the equator to minimize this
rekrunner wrote:
malmo wrote:
I'm still not getting what you mean by "long axis measurement"? A semi-circle has a precise definition. A straight line has a precise defintion. If you have an accurate measuring device then the nominal and actual length of a track can be measured.
In the first post, the OP told us he "decided to measure just the diameter" of the two tracks.
It is the white lines in the pictures.
Thinking "diameter" was the wrong term for a track shaped object, I called it the "long axis".
With this single measurement, even assuming it is infinitely accurate (and no other errors), we cannot yet conclude the track was short, because it does not give us the length of the radius nor the length of the straight.
That is all I'm saying.
I see the problem here -- Houston we have a nomenclature problem.
malmo wrote:
Lofty Goals wrote:
Look, a lot of Monaco results seem too good to be true, .
I've never understood way? Perfect track, perfect weather, in an enclosed stadium with no wind, and the most important meet of the year. Easy for me to see why the results are so good.
Fair enough. I'm just an amateur who'd be happy to run within 2 minutes of Cheptegei, so I'll trust your opinion more than my own. FWIW, I've never thought Monaco was short, I just think that someone looking at the times and thinking that is not totally crazy.
In fact, I think Cheptegei's record is a great example of what you're talking about. He ran 12:35 in Monaco because he went specifically to Monaco to run fast. He probably could run that fast in Brussels or Stockholm or at my local HS track, but he went to Monaco because it is the meet to run fast. Running close to a WR requires more than just WR fitness, and it seems like Monaco does the best job of creating the perfect environment.
It's also one of the highest concentration of wealth in the world. Beautiful weather, year round.
The track is just out of view, lower left.
https://upload.wikimedia.org/wikipedia/commons/d/da/Panorama_von_Monaco-La_Turbie.jpg
malmo wrote:
https://upload.wikimedia.org/wikipedia/commons/c/c1/Monaco005.jpg
I usually stay in the Marriott just adjacent to the stadium (near the stadium arches). The Marriott is actually in France and the stadium is in Monaco.
