2025 SWIM OPEN STOCKHOLM
- Saturday, April 12th – Tuesday, April 15th
- Stockholm, Sweden
- LCM (50m)
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- Entries/Live Results
- Livestream (Pay-To-Watch)
After nearly 16 years, Paul Biedermann’s super-suited 400 freestyle world record of 3:40.07 has finally fallen. 23-year-old Lukas Märtens scorched a 3:39.96 to shave 0.11 off the longstanding mark during today’s Stockholm Open. Märtens had previously ranked as the 4th-fastest man in history before today’s world record performance.
Just like in the Olympic final—where Märtens claimed gold with a winning time of 3:41.78—he took the race out aggressively, flipping at 1:47.55 at the halfway turn. That split was nearly 3.5 seconds under Biedermann’s world record pace and more than a second quicker than his own personal best pace, which was already just 0.26 off Biedermann’s mark.
See the full splits breakdown between the new and old world records below, in addition to Märtens’ previous best time.
Splits Comparison:
| Märtens’ New World Record | Biedermann’s Former World Record | Märtens’ Previous Best Time | |
| 50m | 24.75 | 26.29 | 25.00 |
| 100m | 27.15 (51.90) | 28.13 (54.42) | 27.37 (52.37) |
| 150m | 27.75 | 28.01 | 27.87 |
| 200m | 27.90 (55.65/1:47.55) | 28.59 (56.60/1:51.02) | 28.35 (56.22/1:48.59) |
| 250m | 28.28 | 27.76 | 28.21 |
| 300m | 28.18 (56.46) | 28.39 (56.15) | 28.01 (56.22) |
| 350m | 28.38 | 27.13 | 28.12 |
| 400m | 27.57 (55.95/1:52.41) | 25.77 (52.90/1:49.05) | 27.40 (55.52/1:51.74) |
| Total Time | 3:39.96 | 3:40.07 | 3:40.33 |
Top 10 Men’s LCM 400 Freestyle Performers All-Time:
- Lukas Märtens (GER) – 3:39.96, 2025
- Paul Biedermann (GER) – 3:40.07, 2009
- Ian Thorpe (AUS) – 3:40.08, 2002
- Sun Yang (CHN) – 3:40.14, 2012
- Sam Short (AUS) – 3:40.68, 2023
- Ahmed Hafnaoui (TUN) – 3:40.70, 2023
- Ous Mellouli (TUN) – 3:41.11, 2009
- Elijah Winnington (AUS) – 3:41.22, 2022
- Lin Zhang (CHN) – 3:41.35, 2009
- Park Tae Hwan (KOR) – 3:41.53, 2010
Märtens’ swim today was significant not just for breaking a long-standing record, but because Biedermann’s 2009 record was set in a now-banned super-suit. That era saw suits made with polyurethane, drastically reducing drag and leading to a wave of world records—67 in 2009 alone. The use of these suits helped swimmers achieve faster finishes, which is part of the reason why Märtens was so far ahead of record pace through the front half of his race. In 2010, World Aquatics banned such suits, requiring swimsuits to be made only from textile materials.
Biedermann congratulated Märtens on his swim on Instagram today, saying, “Congratulations! What an incredible performance. I am so happy that the record stays in Saxony-Anhalt.”
Before Biedermann dipped under the record, Australian legend Ian Thorpe held it with his 3:40.08 from 2002.
Märtens narrowed his focus in 2024, and the results have followed. Previously juggling the 200, 400, 800, and 1500 free events, the Bernd Berkhan-trained star shifted his emphasis to the 200 and 400 free last year and quickly reaped the rewards.
After earning three consecutive World Championship medals in the 400 free—silver in 2022 and bronze in both 2023 and 2024—Märtens captured the aforementioned Olympic gold in Paris, following his #4 all-time performance at the German Open. That performance made him the swiftest man in the world last year in the event. At the same meet, he clocked a personal best of 1:44.14 in the 200 free, ranking him #2 globally. In Paris, the now 23-year-old finished 5th in the 200 free and also reached the final of the 200 backstroke, placing 8th in 1:55.97.
Highlights Video:
*We will embed a full race video when one becomes available.
Just realized something else for the moment 400, 800, and the 1500 all have their records in the 30s as in 3:30s, 7:30s, and 14:30s don’t know if it’ll be that way for the reminder of the year but thought that was an interesting thing to point out now
To add to this haven’t seen a 10s place like this since at least 2001 when the 8-1500 got taken under the 40s and before that we had the 100-1500 in the 40 something second place
Florian Wellbrock 14:38.27. Still got it.
Martens was “only” 1:45.55 in the 200free today. I’m not sure how that’s even possible given how fast he was out in the 4
Maybe the emotions of the WR took over him ahaha
Been there after a swim like that. Broke 5 in the 500 at mid season for the first time by several seconds then the next day missed my 200 PB by .5 leading off a relay because I was too excited after the race it wasn’t like I had a very fast pb in the 200 either. It’s real but now I hope he just has an insanely fast worlds could mean we end up seeing a sub 1:44 podium for the first time since 2009 in Singapore (god I hope that happens).
Tom Dean swam a pretty weak relay swim after he’d won gold in the 200 free in Tokyo. Perhaps Lukas didn’t sleep very well last night!
Emotions are a funny thing.
Lukas went 1:45.55 in the 200. Was hoping a better time considering the 400. He was 51.95 at the 100, slower that his 51.90 in the 400, that’s a bit strange
Feel like this should have more comments. This is a huge deal to me. One of the legendary barriers in the sport but it has less comments than who replaces Greg Meehan at Stanford.
If the # of comments was weighted by the level of achievement this would be up there. But this is an American website with primarily American traffic, and Stanford women’s swimming has long been a huge topic of debate in the comments here (hello, relay names guy).
Agree, based on the significance of this swim it feels like it warrants 500-1000 comments.
If he were American, there’d be zillions of comments!
World still in shock
The year is 2050. Nobody has sniffed Lochte’s 2 back textile record, much less perisol’s WR. Zhang Lin 800 still hilariously unchallenged
50 free goes down by then as well as 2 free by a prodigee
Of the 4 records you mentioned, 3 of them may well fall this olympic cycle. Only the 800m i don’t see it go
That 800…
Maybe the 16 year old Turkish swimmer, Kuzey Tuncelli, may be able to challenge it in a few years if he keeps up the trajectory.
Not sure he will ever have the necessary 400 speed to do it. He turns 18 this year.
I agree with him not having the speed, but he seems to be able to continue with the same speed. You’re right he is a year older than I thought. I looked it up and it looks like his bday is the end of August so let’s see how much time he will drop during the race season this year.
If he goes something like 14.35 for the 1500, then I would argue he has the 1500 in his sights and then he might be sub-7.40.
We’ll see I guess. 18 is a weird age. I do not know what his plans are for university. That can make or break the rest of his career.
Thought this must of been short course time at first then nearly fell off my seat. Wow. 🤩
*must have
People dislike your fact. I wonder why
Now that the floodgate is open, do we think someone will join Lukas in the sub-3:40 club in Singapore? I’d say 2 other swimmers will do so.