Systematically fluctuating split times suggest ‘whirlpool’ current at BCN2013

Upon arrival to the Faroes again, my dear brother Bartal points out an interesting systematic variation in the split times from the FINA 2013 World Swimming Championships, that Danish Eurosport commentators pointed out and he then dug into analytically. That there seems to have been a rotating current in the Barcelona pool, that made swimmers in the outer lanes swim every other length fast or slow, depending on which way they swum, with mirrored results on the other side of the pool. Interesting also because people in the Faroe camp noticed and discussed exactly the same phenomena from observing our swimmer Pál Joensen, with about the same conclusion as the guys on Eurosport, without knowing anything about the discussion there. And because a similar ‘swirling current’ theory is being described now here on the blog AstuteCrunch, as mentioned on SwimVortex. Plus here on SwimmingWorld, with specialists from the Counsilman Center on Indiana University as scientific backup.

Now, for the distance swimmers, and maybe all swimmers swimming an even number of lengths, a current shouldn’t pose that big a problem. You get as much as you lose, though maybe suffering a bit of power sapping from trying to follow the competition while swimming against the current every other length. But for the 50 meter sprint events, a current would be devastating to the fairness of both the competition and history, especially if it wasn’t equal on all lanes. Bartal has analyzed a lot of data from BCN2013, and feels pretty sure that there at least on paper seems to have been a rotating, swirling, ‘whirlpool’ current in the Palau Sant Jordi pool.

While Pál competed in Barcelona, people in our camp began to notice that he swam systematically every other length fast and every other length slow, with about the same amount of fluctuation every lap. It was of a significant magnitude of about half a second. Pál only breathes to his right side, so they also noticed that it was when he was facing away from the center lanes during breaths, that he swam slower. The theory developed, that maybe it was because he stressed from seeing the main contenders, that he could swim faster when not seeing them. As he was to switch side of the pool from prelims to final, they predicted that the fluctuation would be opposite there. And yes, that happened.

Bartal produced the following diagrams from split times in the men’s 1500 freestyle, that show very similar patterns of up-and-down fluctuations on lane 2, with mirrored results on lane 8, for *all* swimmers on those lanes. All swimmers swim faster in one direction and slower in the other, with mirrored results on the other side of the pool.

Men’s 1500m Freestyle, Lane 2

Men’s 1500m Freestyle, Lane 8

Now, Bartal tells me that the Danish commentators had exactly the same theory from observing Pál, as mentioned without me or the others in Barcelona knowing anything about it. That Pál swam faster when not seing the main contenders during breaths. With the obvious other theory being a rotating current in the pool, which we in Barcelona also discussed and dismissed as being too unimaginable and potentially controversial, with all the experts on hand in Barcelona.

Here is them discussing this (in Danish) during the 800 prelims

And here again later in the 800 prelims

And again in the 1500 prelims

And here in the 1500 final

Pál’s mentor and longtime now former coach Jón Bjarnason also noticed these fluctuations from watching Pál back in the Faroes, as described in Faroese newspaper Sosialurin on Monday 5 August 2013. The relevant excerpt translated from Faroese:

‘Already at 150 meters I see that he loses a whole second per 100 meters. It is when he breathes towards the center, where he sees the others, that he loses time. I don’t know if he is fighting something [technical] that should make it better, rather than just fighting for it. The split-times clearly show that something is not right when he breathes towards the center, says Jón Bjarnason, former coach of Pál.’

If there was a ‘whirlpooling’ effect in Barcelona, it would be especially unfair in the 50 meter sprint events, as they only swim one length and therefore don’t ‘get as much as they lose’. From analyzing split times, it seems that there was a following current from lane 0 to 3 and a countercurrent from lane 6 to 9, when swimming from the start blocks in even number events (100, 200, etc). The 50 meter races start from the opposite end of the pool, which means that the following current would be from lane 6 to 9. In Barcelona, all medals in the 50 meter races were won on lane 4-8 (with lane 9 not used in finals), except Jessica Hardy’s bronze medal and American record on lane 3 in the women’s 50 breaststroke final. And both world records in the women’s 50 breaststroke were set on lane 5.

Men

• 50 back: gold (lane 4), silver (5), bronze (6)
• 50 breast: gold (4), silver (6), bronze (8)
• 50 free: gold (6), silver (7), bronze (8)
• 50 fly: gold (5), silver (8), bronze (6)

Women

• 50 back: gold (lane 6), silver (4), bronze (5)
• 50 breast: gold (5), silver (4), bronze (3)
• 50 free: gold (5), silver (4), bronze (6)
• 50 fly: gold (4), silver (8), bronze (5)

Medal breakdown per lane in 50 events

In the longer events (100 and upwards), a rotating current would only give the center lanes an unfair advantage compared to the outer lanes in the event, but not compared to history (world records etc), as they in optimum circumstances would only have no current. While the outer lanes in my personal opinion are in best case unaffected by the current (as they get as much following current as they get countercurrent), and in worst case disadvantaged. The four world records in the 100 and upwards were all set on lane 4 or 5, which in case of a rotating current would be the center lanes with the least amount of current.

Of course, it doesn’t really prove anything that the center lanes produce world records, as the favorites and therefore potential world-record breakers are positioned there. But it doesn’t disprove it either.

World records at BCN 2013

• 50 breast, Yuliya Efimova 29.78 (lane 5)
• 50 breast, Ruta Meilutyte 29.48 (lane 5)
• 100 breast, Ruta Meilutyte 1:04.35 (lane 4)
• 200 breast, Rikke Møller Pedersen 2:19.11 (lane 4)
• 800 free, Katie Ledecky 8:13.86 (lane 4)
• 1500 free, Katie Ledecky 14:35.53 (lane 5)

Bartal has been analyzing all split times in the 1500 meter races, and observes a systematic fluctuation in the outer lanes, compared to the center lanes. With mirrored fluctuation depending on which side of outer lanes they were swimming on. We see the same mirrored split time pattern with Daniel Fogg and Michael McBroom as with Pál, as an example of other swimmers who switched from swimming in one side of the outer lanes to the other).

Still really sceptical that a thing like this could happen at the World Championships, we have been discussing this theory with capable people in and out of swimming, without finding any good argument that contradicts the rotating current theory. And then, now, that new blog AstuteCrunch describes the exact same theory, titled “The Barcelona Swirl”. And SwimmingWorld, with analytical muscle from the Councilman Center at Indiana University.

Now, please don’t take this as sour grapes, as we the Faroese were extremely happy with these World Championships. Except for some minor niggles as for instance dodgy internet service at the hotel, almost everything ran smooth and seemed optimally organized, or at least as optimal as I have experienced it. We got two places in the final and four Faroese records (the one in a 50 meter event in lane 6), and we don’t feel that it was a possible current that made the big difference in Pál’s results. Please excuse me if this matter already has been discussed and explained by others, as I as mentioned have been suffering from dodgy internet and a tight schedule and World Champs TV coverage in a language I don’t understand. The patterns we see in the numbers might very well just be a statistical fluke, or because of some other phenomena like lighting or scoreboard view or whatever.

But it is still interesting, that these systematic fluctuations were observed simultaneously by us and the guys at Eurosport, and that the one coach that best knows Pál Joensen didn’t recognize it as a normal pattern of Pál. It is extremely interesting to see now that someone else on AstuteCrunch has made the same observations, resulting in as good as the same theory as us. I am *not* ready to proclaim that there was a rotating current in Palau Sant Jordi, mainly because that would be so extremely controversial. But it would sure be the easiest way to reproduce such systematic fluctuations.