Slow waters in Paris: The puzzle of missing world records at the Olympics

As the Paris Olympics 2024 enters its sixth day, only one world record has been set in the swimming events

The Paris Olympics this week have seen an outpouring of effort and emotion, but one thing remains conspicuously absent: world records. The pool at La Defense Arena, the epicentre of aquatic events, has become a focal point of concern as athletes and officials alike are left scratching their heads over the scarcity of record-breaking performances.

As the games enter their sixth day, only one world record has been set in the swimming events. This stands in stark contrast to the Tokyo Olympics in 2021, where six new records were established, and the Rio Games in 2016, which saw eight. Even the much-anticipated women’s 400 metre freestyle – hailed as the “race of the century” – failed to deliver any record-breaking times, despite the presence of swimming powerhouses Ariarne Titmus (Australia), Summer McIntosh (Canada), and Katie Ledecky (United States).

 

While winning a medal remains the ultimate goal, the near-absence of the letters "WR" next to finishing times on the scoreboard has sparked a flurry of speculation. Coaches, competitors, and commentators are searching for explanations, with some pointing fingers at unexpected sources.

Blame the pool?

A growing number of athletes, including Titmus, have voiced concerns over the games' logistics – from accommodation to food and transport. However, the pool itself has come under scrutiny, with murmurs of it being a "slow pool" circulating among the swimming community.

The pool at La Defense Arena is indeed shallower than those used in recent Olympics. At 2.15 metres deep, it meets the required minimum depth of 2 metres but falls short of the standard 3 metres seen at the Tokyo and Rio Games.

Why does this matter? When swimmers race through the water, they generate waves that propagate in all directions. Surface waves are usually dampened by gutters at the pool's edge, but waves that travel downwards can bounce off the bottom and return to the surface, creating turbulence that slows swimmers down.

Turbulence can disrupt a swimmer's rhythm and increase water drag, effectively sapping their speed. The theory goes that in a shallower pool, more waves bounce back, increasing turbulence and reducing the likelihood of record-breaking times. But is there truth to this "slow pool" theory?

The science of speed

Roberto Colletto, chief executive of the Italian company responsible for constructing the Paris pool, dismisses these concerns, stating, "On the technical side, there is no problem with the pool." Indeed, scientifically speaking, the theory has its flaws.

Waves bouncing off the pool bottom are fundamentally different from those on the surface. Subsurface waves are essentially sound waves, travelling at approximately 1,500 metres per second in water. The millisecond difference in travel time between a 2.15 metre and a 3 metre deep pool is unlikely to have any significant impact on surface turbulence.

However, surface waves do behave differently in shallower water, travelling more slowly. This slower wave speed could potentially affect swimmers, especially in middle-distance events like the 400 metre freestyle. Elite swimmers often harness the waves they generate to "surf" through the water, adjusting their speed to create a wave with a wavelength close to their body length. The slightly reduced hull velocity in a shallower pool could be causing swimmers to unconsciously adjust their pace, though this effect would be uniform across all competitors, giving no one an unfair advantage.

Psychology or Physics?

The belief in a slow pool might be influencing performances as much as any physical factors. Perception can be a powerful force, especially in a high-pressure environment like the Olympics.

Interestingly, the Australian Olympic Trials at the Brisbane Aquatic Centre – which features a pool just 2 metres deep – saw a world record set in the women’s 200 metre freestyle. This suggests that other factors, perhaps psychological or environmental, may be at play in Paris.

Reaching human limits?

It is also possible that swimmers are approaching the natural limits of human performance, at least until the next breakthrough in technology, training, or nutrition.

In other sports, such as marathon running, the rate of record-breaking has slowed as athletes near the peak of human capability. The men's world record for the marathon has only improved by 8 minutes in the last 60 years, and it is predicted that breaking the two-hour barrier in a competitive event might still be years away.

However, swimming records continue to be broken at a relatively higher rate. At the Tokyo Olympics, three-quarters of the swimming event winners posted faster times than those at the Beijing Games in 2008, despite the controversial ban on performance-enhancing swimsuits.

The Olympic motto, “Faster, higher, stronger,” embodies the relentless pursuit of excellence. But in Paris, it seems that breaking records may take a little more time – and perhaps a deeper understanding of the challenges beneath the surface.

(With agency inputs)