Is Olympic pool’s depth hurting swimmers? As world records hold, mystery rolls on

NANTERRE, France — We are taught, rather early in life, that correlation is not causation.

But something is keeping the world’s best swimmers from swimming their usual fastest at these Summer Games.

Five days into the competition at La Défense Arena, there has not been a single world record set in the pool here, a temporary facility built inside what usually is a rugby and concert venue. And, certainly, with swimmers as talented and dominant as Australia’s Ariarne Titmus, France’s Léon Marchand, or the GOAT, Katie Ledecky, somebody should have caught a heater by now and smoked an existing standard. This is what swimming (and track) is all about, right: going faster, and faster, and faster. Records are shattered, it seems, every year, and sometimes, multiple times a year.

But, so far, the best the best can do has been setting a handful of Olympic records — a substantial accomplishment, to be sure. But not world-beating. None of the three favorites at Saturday’s “Race of the Century,” the women’s 400-meter freestyle, came close to breaking their own individual records.

Similarly, on Tuesday, the four fastest women’s 100-meter backstrokers in history took part in the final. Australia’s Kaylee McKeown won, and set another Olympic record, at 57.33. But she was two-tenths short of the world record 57.13, set just last month at the U.S. trials by Regan Smith, who took home a silver Tuesday. With all that talent in the water, one would expect someone to swim the race of her life, and break Smith’s record. (U.S. swimmer Katharine Berkoff took home the bronze, which USA Swimming said was the 6,000th medal won by a U.S. athlete in modern Olympic history, including both the Summer and Winter Games, and the 600th medal won by a U.S. swimmer.)

But in the world of swimming, where hundredths of a second are the difference between getting on a podium or going home empty-handed, they didn’t come close.

Not that McKeown cared much afterward.

“I think it just is what it is, to be honest with you,” she said. “Whether or not it’s the traveling to the pool — the buses have been quite the ride in. But everyone’s in the same boat. So I think it’s just a matter of putting that at the back of your mind, and just knowing that you’ve done the work to get up and swim. Seeing the times not being, obviously, the greatest, some disappointments, some great swims. They’ve been pretty average. (But) I knew tonight was just a matter of just getting my hand to the wall. That’s all I can really ask for.”

To be sure, this is not something that’s on a swimmer’s mind when they’re going for a gold medal. Nor do most fans care; those here Tuesday were delirious, again, as their national hero, Marchand, easily qualified for Wednesday’s 200-meter butterfly final, trying to double up on gold after winning the 400 IM the other night. Ley-on, Ley-on, they chanted, after he got out of the water. No one cared that the world mark of 1:50.34 set by Hungary’s Kristóf Milák in 2022 was unthreatened.

The focus here has been on the pool itself — and, more accurately, its depth. Olympic swimming pools are usually 3 meters deep. The venue here is only 2.2 meters deep — a far cry from the “Water Cube” at the Beijing Olympics in 2008, which was 10 meters deep, and the site of 25 individual and team world records, and 65 Olympic records. That has led to some speculation that this Games’ pool’s relative lack of depth is creating more turbulence in the water, which is slowing the swimmers down. World Aquatics, swimming’s governing body, recommends pools be three meters in depth, with a minimum of 2.5 meters. France was awarded the Games in 2017 and was allowed to construct the pool at its depth.

“Three meters deep is much better,” says Amandine Aftalion, a senior scientist at the French National Center of Research.

“When you swim, you create a wave, and the wave goes behind and goes under,” she said. “And if the pool is too shallow, the wave reflects from the bottom, and causes the water to be turbulent, and therefore, it slows down the swimmers. … Since 2008, it was advised to have a three-meter deep pool. The minimum (is) two meters. But it’s advised to have three meters, because it’s much better for records and because it limits the waves that reflect on the bottom and create resistance.

“It’s crazy that they built this pool. It’s obvious, because many swimmers are really good. They’re in top shape. They could have broken their records. In the 100-meter breaststroke, they should have done much better. And this is really due to the waves that are created at the bottom.”

The deeper the pool, the theory goes, the more room there is for the waves to dissipate and not wash back over the swimmers.

“It’s obvious, even at my (swimming) level, which is very low,” Aftalion said. “Waves are really something that you can feel. If you swim on the lane that is closest to the side, then you feel that it will create waves that reflect on the side, and go back to you. Or if you swim behind someone, there’s an attractive wave that’s going to pull you. If you swim exactly in the wave of someone, you speed up doing nothing. The wave is something you feel when you swim. If you’re in the sea and try to swim to the beach, at some point you have the impression you cannot swim any longer. It’s not because your body touches the sand. It’s just because when it’s very shallow, the drag force, the resistance force of the water, is very strong. Because the water cannot circulate around you.”

But, the pool has just been resistant to world records, not good swims. Many of the winning times here so far have been better than those of equivalent races at last year’s world championships in Fukuoka, Japan, or better than the times of equivalent races at the 2020 Games in Tokyo. It’s just that they aren’t bending the curve any further than it already bends. Maybe everyone’s just off a little, or the pool isn’t quite deep enough, or … who knows, really?

The Olympic motto is Citius, Altius, Fortius: “Higher, Faster, Stronger.” Not “reasonably high, fast and strong for you know, most people.”

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(Top photo of Regan Smith and Kaylee McKeown in Tuesday’s women’s 100-meter backstroke: Oli Scarff / AFP via Getty Images)