The article says the tolerance is "3 centimeters in each lane," which feels surprisingly high. The longest race is the men's 1500m freestyle, which is 30 lengths of a 50m pool. That means that in the worst case, pool dimension errors can add 0.9m to someone's race -- about half a second of time in the 1500m. I bet there are races where 0.5 seconds makes a big difference.
Tolerance works two ways, so the difference could be 1.8m.
However, I would expect that there is a high correlation between the size lengths of lanes in a single pool, so that one doesn't have one lane 3 centimeters too long and the one next to be 3 centimeters too short. It's weird that the standard doesn't make any requirements on that.
Also, touch plates get installed after the pool is constructed. I would expect those could easily be made to compensate for any size differences. That would leave a size difference at the start, but that's easily fixed, too.
Having said that, every few years or so there's a newspaper article of a swimming pool that gets constructed to be 50m, where the constructors forget about those touch plates.
Also, touch plates get installed after the pool is constructed. I would expect those could easily be made to compensate for any size differences. That would leave a size difference at the start, but that's easily fixed, too.
Maybe I misread the article, but it sounds like the effective length of lane can change depending on various environmental conditions. I suppose you may the touch pad distance easily adjustable, but that would be lots of measuring while the swimmers are in the water.
You could maybe have some sort of system to measure the distance between the two sides of the lane in near-real-time (laser rangefinders can be accurate to ~1mm).
(Attempting to construct a concrete pool to any tighter a tolerance is nearly impossible; the effective length of a pool can change depending on the ambient temperature, the water temperature, and even whether or not there are people in the pool itself.)
Concrete on a footpath gets slots made every step or so, to prevent cracking from heat expansion. It's hardly surprising that concrete the length of the pool could have a centimeter or so of wiggle room.
You got me thinking about what other factors could affect the result at various degrees of precision. By my math [1], the time it takes for the sound of the starting buzzer to reach the ears of swimmers at opposite ends of the pool could actually affect the outcome measured in hundredths of a second. But it's an order of magnitude smaller effect than the lane lengths varying by 3cm. Of course, they could remedy this (and for all I know, maybe they do!) by having one starting buzzer speaker placed at the same distance behind each swimmer.
[1] Each lane is 2.13m wide, so the swimmers in lanes #1 and #8 are 14.91m apart. If the buzzer were placed right next to swimmer 1, it would take ~0.044s longer to reach swimmer 8's ear (using 340.29 m/s as the speed of sound). Or if it were right in the middle between swimmers 4 & 5, it would reach swimmers 4 & 5 ~0.019s before it reached 1 & 8.
For both swimming and track events, each starting block has a speaker to broadcast the gun sound. In the 2012 Olympics, the starting gun was replaced with a fully electronic device.[1]
Ah, cool, thanks for filling me in on that. The fact that the organizers indeed go to that length/expense to remove the ~0.02s advantage a swimmer would otherwise have due to the speed of sound makes it even stranger to me that they'd accept a 3cm difference between lanes, which seems to have an order of magnitude larger effect in long races (per OP's calculations).
I'd also wonder if there isn't some advantage/disadvantage to being one of the two swimmers on either end (#1 or #8) versus any of the others (#2-7) which each have two swimmers on either side of them. I have no idea which way the effect would go, but it would seem to me that there must be some effect at the level of hundredths or thousandths of seconds. Edit: seems there's indeed an advantage to being in the inner lanes, and they account for it by seeding [1]. (This was probably well known to anyone who pays any attention to or knows anything about competitive swimming at all. :)
Differences in wall-to-wall distances at middle and longer distances are less important than in shorter distances. The article uses a 100m race. But consider a 50m race. 3 cm over 5,000 cm is a .06% difference. That's easily 1/100 of a second in a 24 second race.
But in longer races, there are many other factors that add noise to this. For one, swimmers aren't competing in a pool where one has to swim 1,500m and another 1,499m pool. They are making turns. A 3cm different is well within the 'noise' of a flip turn.
Also, there is drafting and bow waves, and other things going on that have a bigger effect than the 3cm per length.
This would only matter for national and world records - swimmers competing in finals are swimming against each other at the same time, under identical pool conditions (ignoring any psychological differences between lanes - e.g. breathing towards your cheering fans and family on odd laps vs. even ones, etc).
I thought so, too, but looking at https://www.rio2016.com/en/swimming-sw-mens-1500m-freestyle-..., there were quite a few differences smaller than that in Rio. 38 vs 39 is 0.03 seconds (in different heats, but qualification for further rounds is on time), 3 vs 4 is 0.24 seconds in the same heat.
And I don't see how the race length would be a factor here, as it doesn't affect the relative difference.
It's only at the really short races that the error becomes smaller than the accuracy of the timing.
The question to ask is why so many races end up so close that we need millisecond precision? For races that end so close, I suspect winner is determined by random chance instead of true differentiation. The length of pool precision is not real concern but rather the possibility that we are hitting human + tech ceiling in this particular sport.
I doubt this means we are hitting the human + tech ceiling. Many runners ran 4:02 miles before Roger Bannister broke the 4 minute mile. That was a mental ceiling.
I suspect a similar mental issue exists in swimming. The goal you're trying to beat is your own world record or whatever you think is achievable at your current fitness. Other swimmers are aiming for the same goal. Then when swimming, you see the swimmer next to you, and he's swimming as fast as he can, you're pushing each other, the end result just may be that you push each other to the point where you get the same time, and sometimes that will be an Olympic or World Record, and sometimes it won't.
The wave-eating lanelines do an excellent job of removing most of the effects of wakes. Turbulance from actual strokes is pretty minimised. Worst case is probably in the butterfly where the wake is maximised.
Many other pool features, including both vents (bottom-mounted and highly deflected/diffused) and gutters (in the 1970s - 1980s usually large, below-deck, now often a set of ground-flush slats into which waves are absorbed) also minimise pool turbulence.
It's not clear whether lane placement affects results, but it's true that the middle lanes are often favored, and qualification systems tend to place better-performing swimmers towards the middle. Here's two non-professional discussions on the matter:
granted anecdotal, but when I was a swimmer lore was that center lanes were the fastest due to currents. They do a lot to counter these things though, special lane ropes, deeper pools etc. If you ever watch a lesser event (like non-olympic) they put less effort into dealing with the turbulence. see: https://youtu.be/Igf8PagbGKU?t=1m9s as an example. look 3-5m behind those guys and see how crazy the water is and its spilling all over the other lanes. Also when they flip turn we used to wonder if it was better to go under your forward current that you were pushing just a second prior.
Its utterly mind-blowing that humans of different races, with vastly different life histories and training regimens, competing in a sport with tremendous physical complexity, can wind up with performance equal to each other, to the limits of our ability to measure it.
There's still some important lesson in the Olympics, despite everything.
But we could fairly easily measure it; we just don't find it worth the trouble.
Also, as to the ties, that's almost purely a political choice made by the sporting body. In rowing, for example, the winner in the Olympic final was decided by looking at the finish photo (http://www.telegraph.co.uk/news/2016/08/13/theres-only-one-g...), with both rowers getting the same time in hundreds of a second.
I doubt they can align six boats to that precision at the start, even with equipment for holding the bows of the boats at the starting line.
> a thousandth-of-a-second constitutes 2.39 millimeters of travel. FINA pool dimension regulations allow a tolerance of 3 centimeters in each lane, more than ten times that amount. [emphasis added]
So by the same argument, they should not measure hundredths either...
Eh, anything less than 0.0125s is 3cm and a tie. Pretty darn close to 0.01s and all you need to do is make sure the pool is accurate to within 2.3cm instead...
Much more interesting to think about the delta between the clock that's accurate to hundredths.
Someone could win with a time of 23.01s vs second places 23.00s... But is the delta really 0.01s, or was second place 23.00999999 with a delta of 0.00000001s?
Well, from my experience, back in my youth, you actually have to hit the board or it wouldn't register touch in so many cases. Then you have to rely on whoever is making the manual measurements for corrections and that is messy.
Not every swimming competition can blow cash on slow motion photo finish cameras.
I guess the rules are in place to make most for most swimmers.
Why don't they apply this same reasoning to rowing races in which the inter-lane variations can be much, much bigger than the margin between finishers?
"In a 50 meter Olympic pool, at the current men’s world record 50m pace, a thousandth-of-a-second constitutes 2.39 millimeters of travel. FINA pool dimension regulations allow a tolerance of 3 centimeters in each lane, more than ten times that amount. Could you time swimmers to a thousandth-of-a-second? Sure, but you couldn’t guarantee the winning swimmer didn’t have a thousandth-of-a-second-shorter course to swim."
If you measure the time the swimmers take very precisely and thus can tell that one swimmer reached the target a few milliseconds earlier, that could be because they are a faster swimmer than the second-placed. Or they could just have had a shorter lane to swim and win despite being slightly slower than the other. They swim around 2.39 mm per ms, and lane differences are allowed to be up to 3 cm, so this can make ~12 ms difference where you don't know where it is from.
why not? The regulation only allows them to be longer than the specified lane length, yes, but that still means that one lane can be shorter than another.
This title is not click bait at all. It presents a question and spends a brief article explaining the exact answer to the question. The answer is too long to fit in the title, and there's no click every paragraph to get to the next one bullcrap.
The olympics cost ~$15 billion to host; an accurate range finding device costs a couple of hundred dollars. Heck, with a 3cm margin of error right now, even a $20 tape measure would be an improvement. I'm sure they can afford it :P
> expanding and contracting as the temperature changes.
So measure and adjust the adjustable end-plates a few minutes before each round starts? How rapidly can the temperature change? (I have no idea, but I'm struggling to imagine it changing a huge amount in a small amount of time)
> think about the false start measurement devices. Are those accurate to a a microsecond?
I have no idea, but I don't see why not. 10,000 FPS cameras are available on the general market already, so you could record each swimmer's start and adjust the timings as if they had all started at the same moment :)
I'm sure there is - I'd like to know what the real problems are, because I'm pretty certain that "we don't have the technology to accurately measure 50m" can't be the whole story :)
If the presence or absence of people can affect the size, wouldn't the fact that swimmers start out of water and dive in screw this up?
Unless the boards were mechanized/able to adjust after the fact to maintain the correct distance despite changes to the pool environment. I was imagining setting up the boards prior to the race, but if they are responsive that's different.
The article is incredibly short and addresses what the title promises unbelievably succinctly.
While you called it clickbait, you quoted literally 35.7% of it (577 of its 1613 characters) to show your point, and what you left out was interesting history.
I think it's really rude of you to do this and use the word click bait.
