How to use the Blood Oxygen app on your Apple Watch

The Apple Lookout man has evolved to become a smartwatch that isn't merely another screen to keep an eye on for your steady stream of notifications or to hit the skip button on your gym playlist without having to reach for your phone.

It'due south also emerged as a identify you lot can turn to if you intendance about keeping a closer heart on your health and existence somewhere that tin can do a pretty admirable chore of tracking your fitness too.

If you opt for the Apple Lookout Series 6 or 7, then you'll go the all-time that Apple has to offer in wrist smarts. That includes its new blood oxygen sensor, which might not be a new innovation for wearables, only is the kickoff time Apple has offered the power to take blood oxygen measurements from i of its watches.

So what's the big deal about measuring claret oxygen levels? How practise you do it on the Apple Watch and why would y'all want to do information technology? Here's everything y'all need to know nearly the Blood Oxygen app on the Apple Watch and why you might want to start using it.

What is blood oxygen?

Before getting into how and why Apple tree lets you lot measure out it, let's become into exactly what we mean past blood oxygen. In its simplest form, information technology refers to the amount of oxygen present in your cherry claret cells, which behave that oxygen all around the body.

That oxygen is the body's fuel and it's vital for every part it performs to go along us alive. If the body is struggling to take in the advisable amount of oxygen it needs, it may struggle to carry out those functions properly and that's when y'all might experience low blood oxygen levels and issues that tin be equally a result of those lower levels.

Apple Watch 6 Blood Oxygen app — (Image credit: Michael Sawh)

What can cause blood oxygen levels to exist low?

There's a variety of causes for blood oxygen levels in the body to drop. Atmospheric condition like asthma, infections like pneumonia and respiratory viruses and illnesses like Covid-19 can touch on on the body's ability to get oxygen where it needs to be causing levels to fall.

Being in high distance environments where oxygen in the atmosphere becomes lower than normal is also some other scenario where you tin can experience blood oxygen levels to drop. You may and then experience symptoms like headaches, dizziness, confusion and shortness of jiff.

It's rare for someone to experience blood oxygen levels that are as well high and would be ordinarily associated with someone who requires assisted oxygen support.

How can y'all use blood oxygen data on the Apple tree Watch?

Correct now, Apple will let y'all accept on the spot measurements and monitor blood oxygen levels during the day and while comatose. Apple says the data and measurements generated by its blood oxygen sensor are just designed for general fitness and health purposes. So for those hoping they tin utilize information technology in a similar way to a dedicated pulse oximeter device to offering more serious health insights that could insinuate to some issues tied to low claret oxygen levels, that's non the case with the Apple tree Watch. At least, not notwithstanding it isn't.

Then what does Apple tree mean by 'full general fitness and wellness purposes'? Well, Apple tree doesn't get into whatsoever detail well-nigh that really, and then information technology's very much open to estimation. Ane of the ways it could be utilised is in the altitude scenario we mentioned, keeping tabs on your torso'due south levels when oxygen concentration in the atmosphere is lower to encounter how information technology's responding to the conditions. Information technology'southward something that Garmin does with the pulse ox sensor it includes in many of its watches.

It could potentially also offering a window into training recovery, peculiarly as there's an increased need on oxygen use during do. Slightly lower blood oxygen levels may exist an indication that you're still recovering from a tough workout or block of training and may exist a prompt to consider a rest twenty-four hour period before hitting it hard once again.

Over again, to clarify, Apple will not prompt you based on whether you're off for a hike at loftier distance or working harder in workouts than normal. This is very much on the user to brand use of the data in this way if they find it useful and insightful.

It's not a piece of data you're going to want to bank check during exercise. It's not going to offer annihilation really of value and is really a challenging thing to do to try and take a measurement on the move, which we'll get into more later.

What is a normal claret oxygen level?

Like other smartwatches and fitness trackers that offer to measure out claret oxygen levels, your measurements volition be presented as a percentage. As stated by Apple tree and past the likes of key wellness bodies like the WHO, a blood oxygen level of 95-100% is considered normal. Beneath that, and information technology might be an indication of an issue. Once more though, Apple tree states its app, sensor and measurements aren't to be used for medical purposes, and so do keep that in mind.

Which Apple Watch can measure blood oxygen?

Currently, the Apple tree Watch half dozen and seven are the only ones capable of monitoring blood oxygen levels. Y'all can imagine the Apple tree Watch viii and the next-generation Apple Scout SE volition also pack the sensor technology when they get in on the scene, too.

The Claret Oxygen app is available in sure countries and regions, which you can check hither. Apple too says the feature is designed for users aged 18 and over.

How does the Apple tree Scout measure blood oxygen levels?

The engineering that makes information technology all happen is congenital into the optical heart rate sensor found on the back of the Apple Watch Series six and 7. Like its heart rate sensor, the process is all near lights.

When it'southward time to accept a measurement, that sensor shines red and dark-green LEDs as well as infrared lite onto blood vessels in the wrist. Unlike pulse oximeters, that light is not sent through the trunk. Instead, photodiodes that convert low-cal into electrical electric current measure how much low-cal is reflected back to the back of the Watch.

That data is so crunched by Apple's algorithms to piece of work out the colour of the blood that's been detected. Bright crimson claret or Arterial blood, carries more oxygen while dark cherry venous blood carries less.

So it'due south able to accept measurements from that more oxygen-rich blood that'southward taken from the heart and sent around the residuum of the body to give you that claret oxygen level in a percentage.

How to take a blood oxygen measurement on the Apple Watch

The first affair you lot demand to do is make certain your Apple Watch is running the latest version of WatchOS and you're using an iPhone 6S or newer running iOS fourteen.

Next, go to the Watch app on your iPhone and then to the My Watch section. Scroll downwardly to find the Claret Oxygen app and tap to open up. From here y'all tin toggle on the ability to take blood oxygen measurements.

Yous can as well choose to enable the Watch to take claret oxygen measurements during sleep tracking and in Movie house modes. Or y'all tin can plough it off if you lot're concerned the red low-cal used to track it might go a nuisance.

Back on your Apple Sentry, select the Blood Oxygen app. If it'due south your first time taking a measurement, y'all'll exist given some tips to make sure you get a good measurement.

And so things like making sure your Watch is snug on your wrist but not on besides tight. Likewise keeping your watch screen facing upwards and resting your wrist on a table tin better readings besides.

When yous're ready to have a reading, hit the digital crown and readings volition have fifteen seconds. Once completed you'll get a measurement in a percentage and note that yous can view your data in the Apple Health app.

Where to discover claret oxygen measurements in Apple tree Health

If you desire to encounter a record of all readings taken, forth with a refresher on what the information means, head inside of the Apple Health app on your iPhone, go to Browse and and so look for the tab called Vitals. If y'all've taken a claret oxygen measurement or been monitoring it during slumber, you'll be able to view your information here.

You'll also be able to view daily, weekly, monthly and yearly data. Select Testify More Blood Oxygen Information and you can also view blood oxygen level ranges over those same periods as well every bit daily averages.

Apple Blood Oxygen readings — (Image credit: Apple)

Are there other Apple tree Watch apps that can utilize the blood oxygen sensor?

Right now, the only way to brand use of that blood oxygen sensor is past using Apple'due south own Claret Oxygen app. That'southward non to say that won't alter in the time to come.

Simply like there are plenty of apps that now brand use of Apple's heart rate monitor applied science, it wouldn't be at all surprising if something similar happened with its claret oxygen sensor too.

It will require Apple to open upwards access to developers, so only time volition tell when or if plans to then will materialize in an upcoming watchOS software update.

How accurate is measuring blood oxygen from the wrist?

It'southward smashing that Apple is able to offering this piece of data, but is information technology actually reliable? Well, just like using light-based technology to measure heart rate from the wrist, it'southward using a similar method to have claret oxygen measurements. That does bring some like issues in regards to getting accurate data or information at all.

Apple outlines some factors that could bear on on getting reliable measurements including having tattoos or experiencing depression skin perfusion, which can be caused past being in cold environments. Y'all may struggle to get readings if your center rate is too high too.

Move and moving your wrist around tin can affect readings, just as information technology does on other smartwatches and fitness trackers that measure out blood oxygen. It'due south likely a reason why Apple and the likes of Fitbit choose to take measurements during sleep where that motion upshot is reduced.

There'due south also reasons why in the medical realms, using a pulse oximeter that sits on your fingertip to non-invasively take measurements is the favoured approach. From that part of the trunk information technology'southward considered to reduce those potential issues y'all tin experience at the wrist.

Dedicated pulse oximeters have a different light based approach to measuring claret oxygen equally well, sending two wavelengths of calorie-free through body tissue as opposed to the light reflection method used by Apple and others like Garmin, Fitbit and Huawei. Claret also sits closer to the surface skin on the finger making it a better place to accept measurements.

Apple doesn't country how accurate it'south blood oxygen sensor is and likely won't delve into the accurateness word unless it starts making it suitable for medical grade measurements like its ECG heart rate sensor.

This commodity is role of TechRadar's Become Fit in 2022 series – a collection of ideas and guides to help get your new year's wellness goals off to the correct start, whatever your current level of fitness.