Why is the Olympics swimming pool causing slow swimming?

Team GB’s Adam Peaty, for example, did not get within a second of his time from the British Championships in April.

In the women’s 400m freestyle a night earlier it was a similar tale as only one of the eight finalists, the eventual fifth-place finisher, managed to achieve a personal best.

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The other seven women finished an average of more than 1½ seconds behind their top times.

So, is something causing the series of slower-than-expected swimming times? Read on for everything you need to know.

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Why is the Olympics swimming pool causing slow swimming?

There may be a possible explanation for slower-than-expected times: the depth of the pool in Paris.

Swimming’s global governing body, World Aquatics, recommends that Olympic pools should be three metres deep.

However, the pool used in Paris is 2.15, a whole 0.85 metres shallower than the recommended depth, and 0.25 below the new World Aquatics minimum of 2.5m.

In shallower pools, the water that the swimmers displace with their strokes can bounce off the bottom of the pool and make the swim choppy, which in turn can slow the swimmers down.

"It's a tough pool to swim in, tough when you're on an outside lane," Team GB freestyle swimmer Jacob Whittle told The Sun.

"It's just one of them pools, some pools feel great, some pools don't, a few waves, feels a bit strange being a bit shallower, nothing that we can't deal with," he continued.

"It's a bit like swimming in the sea but not to that extent. There's a lot of waves when coming out of the turn.

"But it's nothing to a high extreme, it's like the 0.1 of a second, but it's just something mentally that you have to deal with."

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Meanwhile, Team GB silver medallist Matt Richards told BBC Sport that he wasn't bothered by the depth of the pool.

"Personally I quite like it being a bit shallower. It stops me messing up my breakouts, like I usually do," he said.

"It's the Olympic Games. It's rare you see really, really fast swimming. Often it's about the racing.

"No-one cares about times at the Olympics. It's about where you come on the podium. I don't care about the times. I am here for placement."

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