You don’t

This key fitness metric is crucial for Olympic ski mountaineering, as well as good health.

VO2 max is an important measure of aerobic conditioning, whether you’re an Olympian or just someone hoping to stay healthy.

By Matt Fuchs edited by Lewis asked.

From skating to curling, the exciting sports of the Winter Olympics are backed by a wealth of scientific data. Follow our coverage here to find out more.

When ski mountaineering, or skimo, debuts Thursday at the 2026 Winter Olympics in Milan Cortina, Italy, athletes will compete in a brutal test of aerobic capacity. They will slide their skis down a snow-covered mountainside that is twice as steep as the highest angle of a typical inclined treadmill. And in doing so, they will move uphill at up to 10 kilometers per hour while sucking in low-density air at high altitudes and carrying more than 4 kilograms of equipment.

Such challenges require extraordinary aerobic conditioning, as demonstrated by their “VO₂ max”: the maximum amount of oxygen the body can use per minute during intense exercise. Watching from their couch, many people see no connection between these physical feats and their own workouts. But VO₂ max is a key marker of performance and health, both for elite athletes and everyday people, says Jill Kanaley, an exercise physiologist at the University of Missouri who studies the key fitness metric. “The higher your VO₂ max, the better your performance will be in running or in everyday life,” she says.

On supporting science journalism

If you enjoy this article, please consider supporting our award-winning journalism by subscribe. By purchasing a subscription, you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.

Here’s what skimo teaches us about VO₂ max and why it’s important.

Olympic level VO₂ Max

VO₂ max reflects how efficiently the lungs move oxygen to the blood vessels and how well the vessels deliver that oxygen to the muscles for intense exercise. According to the American College of Sports Medicine, VO₂ max is the gold standard measure of cardiorespiratory fitness.

The average VO₂ max for a 40-year-old is about 35 milliliters per kilogram per minute. For some ski mountaineers, on the other hand, it is in the 80s.

Skimo sprinters are not the only ones VO₂ max phenomena at the Olympic Games. Elite cross-country skiers have some of the highest VO₂ max values recorded, with some having values ​​above 90. Their numbers, on average, are similar to those of skiers, says Verena Menz, an exercise physiologist at the University of Innsbruck in Austria, who studies these athletes. (And it’s not just winter athletes with high VO₂ values: Tour de France cyclists also have peak VO₂ values ​​similar to those of skimo sprinters, and Norwegian triathlete Kristian Blummenfelt recently established what appears to be a world record VO₂ max of 101.1.)

In addition to being good at aerobics, ski mountaineers must walk with massive forcedelivered in less than half a second per step, a cadence comparable to that of many recreational runners. The best skimo athletes have both a VO₂ max and explosive upper and lower body strength in relation to their body weight.

VO₂ Max and health for the average person

VO₂ max isn’t just important for sport: Olympic-level VO₂ max, whether in elite athletes or everyday people, has been linked to exceptional longevity. Even a slight increase in a person’s VO₂ max can lowertheir risk of premature death. Research that analyzed more than 122,000 adults over eight years found that each incremental increase between the lowest and highest VO₂ max was associated with longer survival.

It’s “much easier” to see improvement in low VO₂ max values ​​than it is to improve an already higher value, says Kanaley, who trains. people with diabetes in cardiovascular fitness. With basic exercise, previously sedentary people can increase their VO₂ max by about 20%, helping them perform tasks like climbing stairs and walking hills, Kanaley says.

If you’re already moderately fit, increasing your VO₂ max requires a more specific training program: perform 75 to 80 percent of your exercise at moderate intensities, then do the rest of your workouts at higher intensities, including maximum effort, says Menz. For a runner, this might mean focusing a few sessions on relatively short, intense efforts, like hill sprints.

VO₂ max is measured using a fitness test performed in a commercial laboratory, which analyzes gases from the nose and mouth captured by a mask. Scientists test skimo sprinters by equipping their laboratories to specifically simulate uphill ski mountaineering. “We always test athletes in a sport-specific way,” says Menz. Since sport-specific tests work the same muscle groups and movements that an athlete has trained, factors such as muscle fatigue will not limit them before their cardiovascular system.

VO₂ max isn’t the only attribute worth training for Olympic and everyday fitness. Strength, balance and flexibility are just as important.

However, the average person does not need to track their VO₂ max; they just need to monitor whether their physical performance changes during dedicated training. Take for example the 5k run. “If your times improve over a six-month period,” says Kanaley, “so does your fitness.”

After all, ski mountaineers don’t judge their success by their VO₂ max. They judge it by their overall performance and by the color of their medal.