Summer McIntosh Is Just Third Woman To Hold Six Individual World Records Simultaneously

Last week at the 2025 Canadian Swimming Trials, Summer McIntosh delivered an unforgettable performance. In just five events, she shattered three world records — the 400 free, 200 IM, and 400 IM — and came incredibly close to breaking two more in the 800 free and 200 butterfly.

(Remarkably, she skipped the 200 backstroke and 200 free — events in which she was a strong world-record contender based on her split times in the IM races.)

She already held the world record in the 400 IM, reclaimed the 400 free mark, and set a new world record in the 200 IM.

This wasn’t the first time she toppled three global records at a single meet. At the 2024 World Short Course Championships in December in Budapest, McIntosh also rewrote world bests in the 400 free, 200 butterfly, and 400 IM.

Thanks to that string of achievements, she now holds an astonishing six individual world records simultaneously — a feat exceedingly rare in swimming history.

Only two other female swimmers have ever reached that level:

Katinka Hosszu first reached six simultaneous world records on December 2, 2015, by setting a short-course 400 IM record. She already held the long-course 200 IM, plus the short-course 100 and 200 backstroke and 100 and 200 IM.

She later extended to seven individual world records when she broke the long-course 400 IM record at the Rio 2016 Olympics (August 6, 2016). She maintained seven records until August 12, 2017, when Mireia Belmonte claimed her 400 IM mark in the short course pool. Hosszu retained six simultaneous records until October 26, 2019, when Minna Atherton broke her SC 100  backstroke record. In total, she held six at once for 1,424 days and seven for 371 days.

Sarah Sjostrom went even further by holding eight individual world records simultaneously. On August 3, 2017, she broke the short-course 100 freestyle record. She was already the world‑record holder in long‑course 50 and 100 freestyle, 50 and 100 butterfly, as well as short‑course 50 and 200 freestyle and 100 butterfly. Sjostrom held all eight records simultaneously for three days until Cate Campbell broke her 100 free on August 6. She retained seven records for 84 days, and six records for over five years (1,587 days) between 2017 and 2021.

McIntosh’s current streak places her firmly in elite company—  and it’s easy to imagine her contending for even more records, in both short course and long course. Events like the 200 and 800 free and 200 butterfly (long course), plus the 200 and 800 free and 200 IM (short course), all seem well within her reach in the near future. Will she match, and even surpass, the achievements of Hosszu and Sjostrom in terms of holding several individual world records simultaneously?