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U.S. marathoner breaks 50K world record

CJ Albertson ran 50K in 2:42:30 to beat the previous record by a little over a minute

Photo by: Instagram/cjalbertson

On Sunday, American marathoner CJ Albertson ran 50,000m in 2:42:30 to set a new world record at the distance. The 27-year-old college running coach ran 125 laps of a 400m track near Fresno, Calif., to beat the previous 50K record (which was set in 1988 by South African Thompson Magawana) by more than a minute. Albertson was the lone runner in the event (although he did have pacers), which was organized by Brooks and billed as an official record attempt. 


Magawana vs. Albertson 

Magawana set his 50K record at the 1988 Two Oceans Marathon in South Africa. En route to his win in the 56K race (in which he set what is still the course record of 3:03:44), Magawana passed through 50K in the world’s fastest time.

RELATED: New indoor marathon world record set at 2:17:59

There might be a bit of confusion as to why Albertson’s 50,000m run on the track is being compared to Magawana’s 50K run on roads. In most other types of racing, road and track results are kept separate, but that’s not the case with ultra distances. For example, Joshua Cheptegei owns the world records in both the 5K and 5,000m, but they’re two different times. Even though Magawana ran his 50K best in an ultra on the road, Albertson’s 50,000m track result will be the new record due to a 2014 rule introduced by the International Association of Ultrarunners (IAU).

This change stated that, as of January 2015, world best performances would be ranked by discipline, “no matter what surface [they were] achieved on,” whether that be road, track or indoors. Magawana’s and Albertson’s results may have been run under very different circumstances, but in the eyes of the IAU, they are equal, and the fastest time is considered the record. 

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Adding to the trophy case

This is not Albertson’s first world record. In April 2019, he ran the fastest indoor marathon in history with a 2:17:59 at the Armory in New York City, where he covered more than 200 laps of a 200m track. He has also proven to be quite good at outdoor marathons, boasting a PB of 2:11:49, which he ran at the U.S. Olympic Marathon Trials in February. He finished in seventh place at the Trials, just a few spots away from a spot on the Olympic squad for the Tokyo Games. 


In his run on Sunday, Albertson averaged a blazing-fast pace of 3:15 per kilometre throughout the 50K race. He posted splits of 32:38.21 for 10K and 1:05:06.89 for 20K (which works out to a sub-1:10 half-marathon), and his marathon time would have been around 2:18. He ran incredibly even splits over the course of the run, posting just one lap over 80 seconds (in his first 400m of the race) and running between 76 and 79 seconds for 123 other laps. His final 400m was his fastest of the day, and he somehow found the energy to drop a 66-second lap to close out the 50K. 

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In an Instagram post, Albertson’s wife, Chelsey, wrote a congratulations to her husband, asking, “what’s next?” While Albertson hasn’t hinted at any upcoming projects, Chelsey noted that he always “dreams big,” so whatever he chooses to chase next will likely align well with his other record-breaking achievements. 

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