Yomif Kejelcha wore two wearables for his 56:51 half marathon world record

Ethiopian runner Yomif Kejelcha has smashed the half marathon world record with a time of 56:51 in Buenos Aires. Look a little closer at the race photos, though, and there is an interesting detail: he appears to have completed the record-breaking run with a fitness tracker on each wrist.

Kejelcha won the Media Maratón Ciudad de Buenos Aires on Sunday, August 23, taking 29 seconds off the 57:20 mark Jacob Kiplimo ran in Lisbon earlier this year. The new 56:51 record is still subject to the usual World Athletics ratification process, but it makes Kejelcha the first man to go below 57 minutes in record-eligible conditions.

It was not exactly a cautious race either. Kejelcha initially planned to run at around 2:45 per kilometre, but gradually picked things up before reaching 15km in about 40:41 and 20km in 54:04. World Athletics’ race report also specifically notes that Kejelcha was checking his watch regularly as he started increasing the pace.

Two devices, two different jobs

Footage from Buenos Aires show Kejelcha once again racing with two wearables. On his left wrist is the familiar Coros Pace 3, while his right wrist appears to carry a Whoop MG.

That is not a new combination for him. Kejelcha used the same basic setup at the London Marathon earlier this year.

At first glance, running a half marathon with a tracker on each wrist might seem unnecessary. In reality, the two devices potentially serve very different purposes.

A running watch such as the Pace 3 can provide something Kejelcha clearly used during the race: information he can actually see. Pace, elapsed time, distance and lap data can all sit directly on the wrist, which becomes rather useful when you are trying to average roughly 2:41 per kilometre for an entire half marathon.

WHOOP takes almost the opposite approach. It has no display and is designed around continuous physiological tracking, strain, sleep and recovery rather than giving a runner a screen full of live race metrics.

That combination actually makes quite a lot of sense. One device can handle the immediate job of pacing and recording the run, while the other continues collecting the data that feeds into longer-term recovery and training analysis.

A pretty good advert for keeping things simple

There is another amusing part to all of this. Kejelcha does not appear to be relying on some enormous top-end adventure watch packed with every sensor imaginable.

The Pace 3 launched back in 2023 and sits towards the lighter, cheaper end of the dedicated running-watch market. It was already several generations into its life when Kejelcha used one at the London Marathon earlier this year.

We saw much the same thing in our look at the watches used by the leading runners at the 2026 London Marathon. Several of the fastest athletes in the world were racing with relatively inexpensive running watches rather than the biggest flagship models.

Whatever was happening on Kejelcha’s wrists clearly did not slow him down. He averaged roughly 2:41 per kilometre for 21.1km and crossed the line in 56:51, putting the half marathon world record back in his hands.