​Apple Watch gets new cardio fitness features, as it a brings VO2 Max to the masses

Apple Watch will tell you if your fitness is too low
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Apple has revamped its Apple Watch health metrics, with its all-new cardio fitness notifications.

The feature has launched as part of watchOS 7.2, and will track users' cardio fitness – based on VO2 Max – and will be found in the Apple Health app.

VO2 Max has been part of the Apple Watch in watchOS 7, and appears as a metric in the Fitness app – as well as Apple Health.

Cardio fitness expands the idea of VO2 Max, and will be able to offer scores for people at lower fitness ranges.

Read our reviews: Apple Watch SE | Apple Watch Series 6

For the uninitiated, VO2 Max is one of the purest assessments of your fitness.

VO2 Max refers to the amount of oxygen transferred into the blood – the more you transfer the fitter you are.

While this can only be truly tested in lab conditions, many wearables can estimate the figure. VO2 Max is a fixture of high-end Garmin sports watches.

However, it's usually gleaned from GPS-tracked running activities, so you have to be pretty active to get a score.

But Apple has developed the idea further, and is bringing the same metric to those at the other end of the fitness scale.

Now on the Apple Watch, cardio fitness can be estimated at lower VO2 Max ranges, bringing the assessment to people starting out with fitness, or using it as a powerful motivator.

It's an opt-in metric, so there’s an on-boarding process where you confirm your age, weight, gender, height and confirm if you're taking certain medications. With all that data the Apple Watch can better estimate your VO2 Max.

Once opted in users will be notified on the Apple Watch if they’re deemed to have dangerously low cardio fitness. Once shown, that warning won’t be shown again for a four-month period, so it doesn't become demotivating.

To get this data for those who aren't busy working out, VO2 Max is calculated in the background when you wear the Apple Watch outside.

It will use motion sensors to detect movement and will use the GPS in the background to get an idea of how fast you’re travelling, augmenting the data with your heart rate and the personal stats you outlined during the onboarding, to gauge your fitness.

It’s a clever system, and it’s great to see VO2 Max being used as a cardio assessment for people at lower fitness levels. We’ll be trying it out in the coming days.

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James Stables


James is the co-founder of Wareable, and he has been a technology journalist for 15 years.

He started his career at Future Publishing, James became the features editor of T3 Magazine and T3.com and was a regular contributor to TechRadar – before leaving Future Publishing to found Wareable in 2014.

James has been at the helm of Wareable since 2014 and has become one of the leading experts in wearable technologies globally. He has reviewed, tested, and covered pretty much every wearable on the market, and is passionate about the evolving industry, and wearables helping people achieve healthier and happier lives.

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