How Short Course Swimming Helped Leon Marchand Break A World Record


Short-course swimming might get some flack because competitors spend a good portion of their race underwater, but it turns out that there are still walls and turns in long course, even if fewer than in long course. That means that the techniques from the small pool can also be utilized to help a swimmer in long course.

According to an analysis by human performance researcher Ricardo Peterson Silveira (@rpsportscience on Twitter), short course swimming may have played a big part in French swimmer Leon Marchand taking down Michael Phelps‘ long-standing World Record in the 400 IM at the 2023 World Championships in Fukuoka on Sunday.

According to Silveira’s study, the difference in Marchand’s improvement came from his improvements underwater. The combined time it took for Marchand to swim 15 meters off of each wall in his 2023 Worlds race was 2.04 seconds faster than it was at the 2022 Worlds in Budapest, where he set his previous best time. In total, Marchand swam a time of 4:02.50 on Sunday, which is 1.78 seconds faster than his 2022 Worlds time of 4:04.22.

Meanwhile, Silveira found that Marchand’s performance on the surface in Fukuoka wasn’t much different than it was in Budapest, as he had similar swimming speed, stroke count, and stroke frequency in both meets.

The majority of a swimmer’s first 15 meters off each wall is spent underwater, which is why underwaters are such a crucial aspect in short course swimming but are less emphasized in long course. Underwaters are one of Marchand’s biggest strength—Phelps even said on the 400 IM NBC broadcast that Marchand pushes his underwaters to 15 meters at every single wall.

Marchand, who is a rising junior at Arizona State, is arguably the best short course yards swimmer in the NCAA. Prior to breaking the 400 IM world record, he shaved over three seconds off the NCAA record in the event this March, which culminated in a 3:28.82 clocked at the 2023 Championships.

To see how Marchand’s underwaters have gotten faster over the last year, take a look at his 400 IM from 2022 and 2023 in the videos down below (courtesy of NBC sports):

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1 month ago

I don’t know if Marchand is going to race the 200 m breastroke, as the semis are 13 or 10 min before the 200 IM final, but what concerns me the most is his ability to maintain such a high level during the full week. There are different scenarii possible:
1- the best one would look like what he did during the NCAA season, where he was able to perform in every race and break several records.
2- the worst would be what he showed during the french championships, where he broke the 200 m breaststroke french record (this was his first race) and then lacked of energy for the remaining events.
3- the most likely, in… Read more »

Eric Angle
Reply to  tchigo
1 month ago

I don’t think it’s realistic for Marchand to swim both the 200 breast and 200 IM. The 200 breast semi is right before the 200 IM final. There isn’t even a women’s event in between. If they’d put the 200 breast final right before the 200 IM semi (or if he had more time to rest between events), then he might be able to attempt the double, but not with the semi before the final.

In Paris there is only a conflict with the 200 breast and 200 fly, where I think he should clearly choose the 200 breast.

Alex Wilson
1 month ago

Having been on the deck on ASU home meets, I have observed that Coach Bowman closely watches carefully and quietly advises swimmers after every race. No yelling!

M d e
Reply to  Alex Wilson
1 month ago

Meanwhile Boxall is one of the loudest presences on pooldeck I’ve ever been around and he has 10 swimmers on the Australian team.

I think for coaches authenticity is the key. Bowman could not be boxall any more than boxall could be bowman.

Alison England
1 month ago

Ah, I see. USA trying to take the credit for Marchand’s improvement?

Reply to  Alison England
1 month ago

Yeah, USA swimmers are the only with underwaters. Are you that much dumb or you push it?

Alison England
Reply to  Mclovin
1 month ago

I am far from ‘dumb’. It was meant as a joke!

By the way…is ‘that much dumb’ actually English language there? It certainly isn’t in England!

1 month ago

How he darted 15m underwater after the 7th turn left me speechless.

Fukuoka Gold
1 month ago

His turn and underwater is sublime.

Regan Smith also has improved on her turns and underwater.

Both have something in common:


1 month ago

hehehe i bet the bathtub haters are loving this article

Reply to  saltie
1 month ago

I think that’s why this article was written.

1 month ago

LOL at the “bathtub” commenters

cant kick cant pull
1 month ago

nowhere ceilings until when everyone does 15m off each wall in long course

About Yanyan Li

Yanyan Li

Although Yanyan wasn't the greatest competitive swimmer, she learned more about the sport of swimming by being her high school swim team's manager for four years. She eventually ventured into the realm of writing and joined SwimSwam in January 2022, where she hopes to contribute to and learn more about …

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