This Triathlon Superstar Just Set the Highest VO2 Max on Record. Or Did He?

Triathlon superstar and Tour de France-fancier Kristian Blummenfelt just became “the fittest man in the world” by setting a record high VO2 Max figure.

Or did he?

Footage posted on Instagram last week shows Blummenfelt, a multiple Ironman world champion and Olympic gold medalist, recording a VO2 Max of 101.1 mL/kg/min.

That’s a measure of aerobic fitness that blows all existing benchmarks way out of the water.

Until last week, the VO2 Max “record” stood at 97.5 mL/kg/min, set in 2012 by teen Norwegian cyclist Oskar Svendsen.

U.S. legend Greg LeMond recorded a VO2 Max of 92.5 when he was at his competitive peak, while modern-era dominator Tadej Pogačar was recently estimated to boast a VO2 Max in the high 90s.

VO2 Max is widely regarded as the “gold standard” indicator of aerobic fitness. Tested via a heinous ramp-to-exhaustion protocol on a trainer or treadmill, it establishes the maximum amount of oxygen the body can utilise per minute, per kilo of bodyweight.

The higher the VO2 Max, the more oxygen that can be transported to working muscles.

‘Big Blu’ and his big VO2

A series of slides posted last week by Blummenfelt includes a clip of the burly Norseman deep in the pain cave in the ugly aftermath of his treadmill-based VO2 Max test.

The video first shows Blummenfet sucking air through his ventilation mask in a state of excess distress.

The camera then pans to the money shot: A computer screen that breaks down the results, revealing that 101.1 mL/kg/min VO2 Max. Blummenfelt did not comment on the score in the blurb that accompanies the post.

Blummenfelt has long been regarded as one of the world’s greatest endurance athletes. Working with acclaimed trainer Olav Aleksandr Bu, he and fellow Norwegian star Gustav Iden dominated world triathlon for years.

Bu is now also chief trainer for the rising Scandinavian WorldTour team, Uno-X Mobility.

The news last week of Blummenfelt’s triple-digit VO2 Max blew up several niche corners of the internet.

Triathlon fans, physiologists, and performance nerds like me all took note.

‘The physiological maths don’t add up’ on Blummenfelt’s record

But not everybody was impressed.

In fact, many piled in on the plausibility of this new record.

UAE Emirates-XRG performance co-ordinator Jeroen Swart – the expert who oversees the training of Pogačar, Isaac del Toro, and the rest of the world’s No.1 team – led a chorus of skepticism on social media.

“Can someone please go to Norway and teach the physiologists how to calibrate a metabolic cart,” Swart wrote on Twitter/X. “Seems we get dodgy VO2 data every second year with wildly inaccurate values and sensational stories about incredible endurance athletes.

“Only ever happens in Norway. Bizarre,” Swart continued, referencing previous record-holder Svendsen and the long list of  Norwegians who have recorded monstrous VO2 Max scores.

Multiple world-leading physiologists piled in to question the accuracy of the “metabolic cart” device used during the test and to point out loopholes in the protocol and results.

Some even questioned the mathematical plausibility of Blummenfelt’s score.

“[This] happens a few too many times, and in a few too many places, to be fair!” acclaimed British researcher Jamie Pringle wrote.

“That the user hasn’t realised the data doesn’t make sense – the physiological maths don’t add up – is really quite eyebrow-raising. That they then put something out to the public doesn’t do anyone any favors,” Pringle wrote.

This won’t be the first time “record” VO2 Max results have been questioned.

As Outside Online contributor Alex Hutchinson once pointed out, the metabolic testing equipment used to conduct these tests isn’t designed “for freaks who can churn through more than seven liters of oxygen per minute.”

Tour de France dream on pause for Blummenfelt

Whether Blummenfelt’s 101.1 is valid or not, it will go down in the record books as a reference-point for peak human performance.

As one commentator gushed, “Blummenfelt’s result isn’t just an extreme fitness stat. It’s a glimpse into how big the human aerobic engine can become when physiology, training structure, and recovery align.”

But it’s how the barrel-chested triathlete expresses his “world best” physiology that really counts.

Blummenfelt missed out on both the Ironman full and 70.3 world championship titles last year and has vowed to go for gold again in 2026. In the longer term, the 31-year-old is all-in on the 2028 LA Olympics.

And remember that rumored switch to the WorldTour and an audacious plan to win the Tour de France? That project is on pause.