Three world records in five days – that’s how 18-year-old Summer McIntosh is making waves at the Canadian Swimming Trials ahead of the 2025 World Aquatics Championships.
On June 11, she shattered her own world record in the 400m individual medley, clocking 4 minutes 23.65 seconds – faster than the 4:24.38 she set just weeks earlier at the 2024 Canadian Olympic Trials.
In total, McIntosh delivered three jaw-dropping performances at the June 7–12 meet. She reclaimed the 400m freestyle world record with a 3:54.18 finish, then rewrote the decade-old 200m individual medley record in 2:05.70.
Here are five things to know about the Canadian teen taking the swimming world by storm:
1. She was Canada’s youngest Olympian in Tokyo
At just 14, McIntosh earned her Olympic spot by winning the 200m freestyle at the 2021 Canadian trials in Toronto. She went on to compete in four events at the delayed 2020 Tokyo Olympics, where her standout performance was a fourth-place finish in the 400m freestyle – breaking the Canadian national record with a time of 4:02.42.
2. She’s already a multi-time world and Olympic champion
Since her Olympic debut, McIntosh has climbed to the top of the podium repeatedly. She won two world titles in 2022 (200m butterfly, 400m individual medley), and repeated the double in 2023. At the 2024 Paris Olympics, she captured three gold medals – in the 200m and 400m individual medley and the 200m butterfly – along with a silver in the 400m freestyle.
Across all major international competitions, she now boasts 14 gold, six silver, and six bronze medals.
3. She broke her first world record at 16
McIntosh made history in 2023 when, at age 16, she set her first world record in the 400m freestyle with a time of 3:56.08. Days later, she took down the 400m individual medley world mark with a 4:25.87 swim. With those victories, she became the first athlete ever to hold both records simultaneously.
4. Athletic talent runs in the family
McIntosh comes from a strong sporting background. Her mother, Jill Horstead, swam for Canada at the 1984 Los Angeles Olympics, finishing ninth in the 200m butterfly. Her older sister Brooke is a top-level figure skater who won the 2025 Spanish national title in pairs alongside Marco Zandron.
5. She’s drawing comparisons to Michael Phelps
While it’s too early to write history, McIntosh is already being compared to the greatest swimmer of all time. At the 2008 Beijing Olympics, Michael Phelps won eight gold medals and broke four individual world records – a legendary feat.
Now, McIntosh is the first swimmer since Phelps to break three individual world records at a single long course meet. As she prepares to compete in five individual events at the upcoming World Aquatics Championships in Singapore (July 11–August 3), she has a chance to match Phelps’ iconic five-gold standard from the 2007 World Championships.
After the Worlds, McIntosh plans to relocate to Austin, Texas, to train under Bob Bowman – the longtime coach of Michael Phelps.
