On August 27, 2012, an 18-year-old Norwegian cyclist named Oskar Svendsen visited a lab in Lillehammer for physiological testing. The tests, which included lactate threshold, efficiency, and VO2 max measurements, had become a standard part of his routine since switching his focus from alpine skiing to cycling three years earlier. But something was different this time. After the testing was finished, the scientists disassembled the metabolic testing equipment, and the next day they shipped it back to the manufacturer to check its calibration: Svendsen’s VO2 max reading had eclipsed the highest value ever recorded.
VO2 max is a measure of how quickly your lungs, heart, and muscles can process oxygen, and it’s synonymous with aerobic fitness. When we talk about extreme feats of endurance, like world records or two-hour marathons, we’re implicitly wondering (in part, at least) about the outer limits of VO2 max. New physiological “records” are a big deal. Though Svendsen was an unknown at the time, rumors of his test traveled quickly—especially since, just two weeks later, he seemingly lived up to his physiological potential by winning the individual time trial at the junior world championships.
Such records are also a cause for great skepticism, though. As I noted last year in an article about the upper limits of VO2 max, bogus readings are fairly common, in part because metabolic testing equipment isn’t really designed for freaks who can churn through more than seven liters of oxygen per minute. The record that Svendsen supposedly broke—a reading of 96 milliliters of oxygen per kilogram of body weight per minute, by cross-country ski legend Bjørn Dæhlie in the 1990s—is viewed with skepticism by many scientists, and was only reported in the press rather than in scientific publications.
The same criticism can no longer be leveled at Svendsen’s reading of 96.7 ml/kg/min. Last week, a team of researchers from Innland University of Applied Sciences in Norway (along with Mayo Clinic physiologist Michael Joyner) published a case report in the Journal of Applied Physiology. Notably, the paper details Svendsen’s entire testing history rather than just a one-off value, building a case that the measurement was legit—and it offers some insight into what happened to Svendsen afterwards.
Before Svendsen started cycling at 15, he was an alpine skier. His training wasn’t particularly intense: one or two workouts a week, plus weekend races during the winter. The regimen was mostly focused on strength, balance, and coordination, so you wouldn’t expect he would have particularly good aerobic fitness. At 15, he started cycling two or three times a week as part of his off-season ski training. He was good at it, so he took a VO2 max test as part of the selection process for a local high school that had a cycling program. His result of 74.6 ml/kg/min, as an essentially untrained teenager, was exceptional: it’s what you’d expect from a serious national-class or even international-class endurance athlete. He passed the selection test.
Over the next few years, Svendsen began training seriously, and his test results responded accordingly. Just six months after his first test, he scored 83.4. The following year, he hit 86.8. And the year after that, he notched his 96.7. His second-highest reading, later in 2012, was 92.8. It’s tempting to wonder whether the record reading was some sort of fluke—a measurement error or a miscalibration. Indeed, one of the section headings in the case report is “Do we believe in the results ourselves?”
The testing machine, for what it’s worth, was properly calibrated, according to the manufacturer. Other readings taken that day were no higher than usual.
It’s also worth looking at the results of a test taken just over three months later, in December 2012. Svendsen registered a 92.8 ml/kg/min, considerably lower than his highest reading. But this was now in the middle of his off-season, and he had gained 2.2 kilograms (4.8 pounds). VO2max is usually expressed relative to your body weight, which means it’s divided by your weight in kilograms. But what the machine actually measures is absolute VO2max, which isn’t divided by weight. The record-setting reading corresponded to an absolute VO2max of 7.397 liters of oxygen per minute; the subsequent off-season test was almost indistinguishable, at 7.307 L/min. Svendsen was still an oxygen processing machine; it’s just that he had packed on a few pounds during his off-season.
Svendsen’s world championship race was his last as a junior. The next year, he moved up the under-23 ranks with a Norwegian pro team called Joker. He had some promising races; he had some disappointing ones. In 2014, two years after his famous test, he decided to take a break from cycling. After 15 months without formal training, during which he mostly ran once or twice a week, he made one final visit to the laboratory. His VO2max was back to 77.0 ml/kg/min—strikingly close to the 74.6 he’d recorded when he first showed up at the lab.
Two things that stand out about Svendsen’s test values are how high they were when he didn’t train, and how much higher they got when he did. Both baseline fitness and trainability have a strong genetic component, and Svendsen appears to have hit the jackpot in both. His weakness, however, was efficiency: his huge aerobic engine provided him with lots of energy to burn, but that didn’t translate to otherworldly power outputs on the bike. Maybe that would have come with a few more years of training, though scientists still aren’t entirely sure what determines cycling efficiency and whether or how it can be improved.
In the end, the real lesson we can take from Svendsen’s story is that physiology isn’t destiny. His high numbers tell us that eventually someone else will come along with similarly high numbers. But to push back the barriers of athletic performance, that someone will need something more—something, perhaps, that can’t be measured in the lab. “The talent is in the head after all,” Svendsen told a Norwegian journalist (according to Google Translate) shortly after quitting cycling. “That’s what you create yourself. The physical is just a bonus.” He’d decided to return to university, and study psychology.
My new book, Endure: Mind, Body, and the Curiously Elastic Limits of Human Performance, with a foreword by Malcolm Gladwell, is now available. For more, join me on Twitter and Facebook, and sign up for the Sweat Science email newsletter.