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Running’s most intense hill workout: Kilian Jornet’s ridiculous one-hour challenge

Jornet shares his toughest training session: run a vertical kilometre followed by a flat 10K, all in less than an hour

Photo by: Instagram/kilianjornet

We don’t expect you to try this at home, but it’s too impressive to ignore. On Monday, Spanish ultrarunning champion Kilian Jornet shared one of his most intense training sessions on Instagram. Dubbed the VK10K, this challenge sees Jornet run a vertical kilometre (meaning 1,000m of elevation gain) followed by a flat 10K. This sounds difficult enough, but he adds a time factor to it and attempts to run the whole thing in less than an hour. Like we said, don’t feel pressured to try this.

Jornet has won so many of the biggest ultramarathons around the world, including the Western States 100 and the Ultra-Trail du Mont-Blanc. He is without a doubt one of the greatest ultrarunners of all time, and this workout shows why. For most people, this wouldn’t even be on their radar as a one-off challenge, but this is an established training session for Jornet. In his Instagram caption he explains how the run works.

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“Run a vertical kilometre, run down easy and run a 10K flat,” he writes. He at least has some break between the intense climb and the quick 10K effort, but running down a steep grade will tire your legs out, too. He says he usually does an “easier” version of the VK10K, with 700m of climbing and a 7K flat run instead, but on Monday he ran true to the challenge’s name. 

He says he started out “speedy” on the vertical kilometre to make up for about 100m of flat and downhill terrain three-quarters of the way through the climb. “That’s a pity, because I believe if it wasn’t for those [flat and downhill] metres it could be a very fast place for a VK,” Jornet adds. He completed the 1,000m climb in 29 minutes and 57 seconds, giving him a hair over 30 minutes to complete his 10K if he wanted to accomplish the VK10K in less than an hour. 

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He writes that he started the 10K “on a semi-conservative pace,” trying to hover around three minutes per kilometre. In the final 2K, he “gave everything” and finished the route in 29 minutes and 42 seconds, bringing his official vK10K time to 59 minutes and 39 seconds. He says the effort caused him to taste blood in his mouth, and his heart rate was understandably skyrocketing throughout, but he made it through with a quick result. 

While most people in the running community can only dream of running a VK10K as quickly as Jornet, you can still run a variation of the workout. Try a V5005K (500m climb followed by 5K flat) or even a V2002K or V1001K. It’s all about challenging yourself, and who knows, maybe you’ll really like the workout’s intensity. 

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