How Often Do Reigning World Champions Win The Olympic Title The Following Year?

The World Aquatics Championships have been held since 1973. Initially with an irregular periodicity (the second edition took place in 1975, and the third in 1978), from 1978 onwards the event began to be held every four years. The only exception was in 1991, when the edition held in Perth, Australia, took place in January – it could even be argued that, during this period, it was part of the 1990 season.

From 2001 onwards, the World Championships began to be held biennially, every two years. As a result, we always have a World Championships the year prior the Olympic Games. As a result, the Worlds have always served as a good preview of what was to come the following year at the Olympics.

And although you’d expect it to be very common for world championship winners to claim gold in the same event the following year at the Olympics, in reality, there haven’t been that many, especially in the last few editions.

Simply analyzing the percentage of 132 individual events contested between the 2004 and 2021 Olympic Games, 54 of them were won by the same swimmers who won them at the previous year’s World Championships, a mark representing 40.9 percent.

(Of course, the Tokyo Olympics in 2021 were held two years after the previous World Championship in 2019, as they were postponed due to the Covid-19 pandemic. But this will bring up an interesting fact later on.)

The curious thing is that this percentage of 40.9 percent does not reflect what has happened over the years.

Percentage of events in which the winner of the World Championships goes on to win the Olympics the year after

At the Athens Olympics in 2004, no less than 16 of the 26 individual events were won by swimmers who had won the same events at the Barcelona Worlds in 2003. This represents 61.5 percent. Swimming legends such as Inge de Bruijn, Yana Klochkova, Ian Thorpe, Grant Hackett and Michael Phelps were among them.

In 2008, the percentage decreased considerably: it became 46.2 percent (12 out of 26). Phelps was responsible for almost half, having won the same five events in Beijing that he had won at the 2007 World Championships in Melbourne.

In 2012, there was another drop in the percentage: nine out of 26, or 34.6 percent. This time, Phelps managed to repeat just one victory he had achieved at the 2011 World Championships, in the 100 butterfly. You could say that in all nine of these events, the heavy favorites won – Missy Franklin in the 200 backstroke, Dana Vollmer in the 100 butterfly, Sun Yang in the 1500 freestyle, Daniel Gyurta in the 200 breaststroke and Ryan Lochte in the 400 IM.

In 2016, another drop: there were eight out of 26, or 30.8 percent. Katie Ledecky won three of those events (200, 400 and 1500 freestyle) and Katinka Hosszu won two (200 IM and 400 IM).

In 2021, a small increase compared to 2016. There were nine events won by the same swimmers from the 2019 World Championships, which represents 32.1 percent — in 2021, there were 28 individual events, with the addition of the men’s 800 freestyle and women’s 1500 freestyle.

This is curious, since the percentage increased, even though there was a two-year gap between the 2019 World Championships and the 2021 Olympics.

Again, it’s interesting to note that most of those nine events where repeat winners were won by overwhelming favorites — for example, Caeleb Dressel in the 50, 100 freestyle, and 100 butterfly, Adam Peaty in the 100 breaststroke, Kristof Milak in the 200 butterfly and Ledecky in the 800 free.

Perhaps the explanation for the percentages being so high in 2004 and 2008 is that there were more heavily favorites, swimmers who today are considered undisputed swimming legends — Phelps, Thorpe, de Bruijn, Klochkova, Aaron Peirsol, Natalie Coughlin, Leisel Jones and Kosuke Kitajima.

With these data, for the 2024 Olympics in Paris, the projection is that between 30 percent and 40 percent of the events will be won by the same swimmers that won at the 2023 Fukuoka World Championships. Which means eight to 11 events.

Given the superiority they displayed, perhaps the heavy favorites to repeat their 2023 world titles with wins in Paris are Sarah Sjostrom (50 free), Ariarne Titmus (400 free), Ledecky (800 and 1500 free), Summer McIntosh (400 IM), Cameron McEvoy (50 free), Qin Haiyang (200 breaststroke) and Leon Marchand (400 IM). This would total eight events. Who are the other candidates?