If you have ever done a hard week of training, checked your Oura app and found the VO2 max number sitting exactly where it was, you are not alone. It is one of the most common questions Oura owners ask, and the answer is reassuring: the feature is working as designed. Cardio fitness changes slowly, and Oura deliberately smooths its estimate so that one big workout cannot swing it. What has changed recently is how you get the number. As of late October 2026, there are two routes: the original six-minute walking test, and a new automatic estimate from Oura Labs that builds the score from your ordinary outdoor workouts. Here is how both work, what to expect from the figure, and why it moves the way it does.
Disclosure: Fitcoin is our product. We are not affiliated with Whoop, Oura, Google, Fitbit, Garmin, Polar, Amazfit, Xiaomi, Samsung, Suunto, Apple, Huawei, Hume Health or any other brand named on this page. We do not sell trackers and we take no affiliate commission. Where Fitcoin appears, it is as the rewards and insights app that reads the data these devices and workouts write to Apple Health or Health Connect. Everything below is a wellness estimate for general fitness, not medical advice.
Where the number lives and what it means
Oura calls this metric Cardio Capacity, and you will find it in the app under My Health, then Heart Health. It is Oura's age-adjusted estimate of VO2 max, the amount of oxygen your body can use during all-out effort, expressed in millilitres per kilogram per minute. When you first open it, the figure you see is not from any test. It is a population estimate based on the age, sex, height and weight in your profile, which is why it can feel oddly specific despite knowing nothing about your fitness yet. Think of it as a placeholder until you give the app some real data.
Oura then sorts your estimate into one of four bands: Peak, High, Fair or Low. These are relative to people of your age and sex rather than an absolute athletic ranking, so a Fair at 55 and a Fair at 25 represent quite different numbers. If you want the broader background on what VO2 max means and why it matters, our Fitbit cardio fitness explainer covers the concept in detail. This page focuses specifically on how Oura calculates it and what changed at the end of October.
You will need a Gen3 ring or newer and an active membership to see any of this; Gen2 rings do not get the Heart Health section. Oura's help pages list the feature on both iOS and Android. Membership is the same fee that unlocks the rest of the detailed app, $5.99 a month or $69.99 a year in the US at the time of our Ring 5 review, and the hardware alone does not include this chart.
The six-minute walking test
The original method, which is still available, is a six-minute walk. Oura combines the distance you cover with your heart rate to estimate your capacity. Because the distance comes from your phone's GPS, a treadmill will not work, and neither will a route that stops you at traffic lights, dips through a tunnel or climbs an unexpected hill. Oura's help article asks for a straight, level path, a phone charged above 20 percent, location services on, and the phone carried with you for the whole walk. The pace should be brisk: as fast as you can comfortably walk without breaking into a jog.
Complete it once and the population placeholder is replaced with a measured estimate. Oura suggests repeating the test roughly once a month if you want to track a trend. Doing it every Monday out of impatience will mostly reveal that a six-minute walk has good days and bad days; a headwind, a heavy bag or a slightly different route is enough to nudge a figure that is meant to describe months of training rather than a single morning.
You can also enter a value manually. If you have had a lab test or you trust the figure from a Garmin or another watch, Oura accepts any number from 1 to 100, labels it with its source, and lets you delete it later. Your other devices do not have to argue with the ring; the estimates can sit alongside each other, which is a sensible design choice. Just resist the urge to average them into a third number of your own invention.
Automatic VO2 max, the October update
The new option is automatic VO2 max in Oura Labs, with the help article updated on 28 October 2026. Switch it on and the walking test becomes optional. Before the first automatic score appears, the app needs two things: at least 30 days of Oura data, and at least five qualifying workouts. A qualifying workout is an outdoor walk, run or hike recorded with GPS location on. Indoor rowing does not count, and neither does an outdoor walk where location permission was declined. The ring has no GPS of its own, so in practice this feature quietly depends on your phone coming along for the walk.
Once those conditions are met, the score updates as further qualifying sessions come in. Oura's own guidance on what to expect is worth remembering: VO2 max typically shifts by around 2 to 5 percent over six to nine months of consistent training. That is why a heroic interval week will not produce a new number overnight. The app is specifically designed not to reward a tailwind or a single great run. If your figure looks stuck, check whether you have five genuine outdoor GPS sessions logged, whether the 30 days have elapsed, and whether you are comparing it to a lab result taken on a bike, which will not match a walking-based estimate even when both are accurate.
So the practical choice is this. If you want a number this weekend, do the six-minute walk on a flat path with your phone in your pocket. If you would rather not think about it, enrol in Labs, keep location on for your regular outdoor walks and runs, and check back in a month. Both are estimates, and neither is the mask-and-treadmill test you would get in a lab.
What a ring can and cannot tell you
A lab VO2 max test is maximal: you go until you cannot go any further. Oura is doing the opposite, inferring your ceiling from a brisk walk or from the heart rate and pace of your everyday GPS sessions, then smoothing the result so that no single workout dominates. This is why runners who also own a Garmin often find Oura's number a little lower and slower to change than their watch. Garmin's algorithms were built to grade workouts; Oura's were built to grade your nights, and this chart is a guest in that app.
Finger-based heart rate during a hard run is also a noisier input than a chest strap or a snug watch, and the automatic estimate inherits that. If your outdoor runs already look messy next to a chest strap, do not expect a precise capacity figure built on top of them. The walking test on a calm day is a cleaner signal, or you can enter the lab value and let Oura's automatic series run as a separate line for comparison.
It is also worth keeping the number in perspective. VO2 max is one of the better predictors of long-term health we have, and it is worth improving, but it is a slow-moving metric by nature, and Oura's version is slower still because it refuses to flatter you. For the nightly side of the same ring, our guides to what a good HRV looks like and what the Oura Ring actually tracks cover the readiness and sleep features, and if you are still deciding whether the subscription is worth it, that question has its own page.
Sources: Oura's Cardio Capacity help article, updated 28 October 2026; the Oura Labs help article on automatic VO2 max; and Oura's Pulse blog post on Cardio Effort and automatic VO2 max, all checked 2 November 2026. We did not run a comparison against a laboratory metabolic cart.
More Oura: Ring 5 review, is the membership worth it?, VO2 max on Fitbit, what the ring measures.
Frequently asked questions
Does the Oura Ring measure VO2 max?
It estimates it. Oura's Cardio Capacity feature uses either a six-minute GPS walking test or, since October 2026, an automatic estimate built from your outdoor GPS workouts. Both are estimates rather than a lab-measured maximal test, and you need a Gen3 ring or newer plus an Oura membership.
How do I get an Oura VO2 max score?
Go to My Health, then Heart Health in the Oura app. Either complete the six-minute walking test on a flat outdoor route with your phone, or enable automatic VO2 max in Oura Labs and wait until you have 30 days of data and five outdoor walks, runs or hikes recorded with GPS.
Why is my Oura VO2 max not changing?
Because real VO2 max changes slowly, typically 2 to 5 percent over six to nine months, and Oura smooths its estimate so one workout cannot move it. If you are using the automatic version, also check that you have at least five qualifying outdoor GPS workouts and 30 days of data.
Can I do the Oura walking test on a treadmill?
No. The test uses GPS distance from your phone, so it needs to be done outdoors on a straight, flat route with location services on and the phone carried with you.
What do Peak, High, Fair and Low mean?
They are Oura's categories for your estimated VO2 max relative to other people of your age and sex. They are not absolute athletic rankings, so a Fair at 55 represents a different number from a Fair at 25.
About the author: Harris Khan is the co-founder and CTO of Fitcoin, a UK fitness-rewards and health-insights app that reads Apple Health and Health Connect.