What is VO2 max and why should you set it up with Apple Watch? Guides

One of the useful and somewhat buried health features on Apple Watch is VO2 max. The measurement can be estimated by Apple Watch when recording specific workouts but it isn’t enabled by default and actually goes by another name. Follow along for a look at how to use VO2 max with Apple Watch and iPhone including why it’s important, how to set it up, and how to view your VO2 max levels.

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Whether you’re new to Apple Watch or have had one for a while and haven’t tracked VO2 max before, it’s a valuable measurement to understand and use.

But since VO2 max tracking isn’t turned on by default and Apple uses the name “Cardio Fitness,” it flies under the radar for many. Here’s how the company describes it:

What is VO2 max and why should you set it up with Apple Watch? Guides

Apple Watch users can view their cardio fitness level in the Health app on iPhone, and receive a notification on Apple Watch if it falls within the low range. Breakthrough technology released in watchOS 7 allows Apple Watch to easily measure low cardio fitness, and today cardio fitness notifications empower users to be more active for dramatic long-term health benefits.

Cardiorespiratory fitness, as measured by VO2 max, is the maximum amount of oxygen the body can use during exercise, and it can be increased through physical activity. Apple Watch already estimates average and higher levels of VO2 max during vigorous outdoor walks, runs, or hikes, which many runners and other athletes monitor to improve performance.

By measuring the “body’s ability to take in, circulate, and use oxygen” Cardio Fitness via VO2 max is a metric that gives a good indication of overall health and can also predict long-term health. While there’s a correlation between low VO2 max and future health issues, you can raise your levels with consistent aerobic exercise 🙂.

Relative VO2 max is expressed as a number between 14 and 60 with Apple Watch/iPhone and represents the amount of milliliters of oxygen used in one minute per kilogram of body weight (mL/kg/min).

Two more great resources to track heart health is with HRV on Apple Watch and the Withings “Vascular Age” feature on its latest Body Cardio smart scale.

How to use VO2 max with Apple Watch and iPhone

Interestingly, Cardio Fitness Levels will show up even for outdoor walk/hike/run workouts that you’ve previously done. You can tap the timeframe icons at the top of Cardio Fitness to see daily, weekly, monthly, and yearly data (see more on this below).

Apple notes that cycling is another great aerobic exercise to improve Cardio Fitness, but for now, it doesn’t look like tracking Cycling workouts on Apple Watch will record VO2 max.