Apple Watch owners can get fit easily with the Activity app. Here's how to track calories burned, time spent exercising (and sitting and standing)  and distance moved with the Apple Watch.

The Apple Watch's Activity app is designed to help you get fit and stay healthy. It does this by setting and tracking three daily targets: to sit less (your target is to stand for at least one minute in each of at least 12 separate hours), to move around more (measured according to the calories you burn), and to log 30 minutes of brisk activity every day.

The Activity app is accessible from the Home screen. Press the Digital Crown to go the Home screen and tap the icon showing three concentric coloured rings - red, green and blue.

How to use the Apple Watch Activity app: Home screen icon

See also: Best Apple Watch apps | Best Apple Watch games | Complete guide to Apple Watch

How to use the Apple Watch Activity app: Setup

Tap 'Get started', and fill in your personal details: sex, age, weight, height and so on. (When entering information, it's generally more accurate to scroll up and down through possible answers using the Digital Crown rather than swiping up and down on the screen.)

Bear in mind that you can skip some of the details if you're in a rush or if, like us, you don't know your height in cm or your weight in pounds. But coming back afterwards to add this information (which presumably helps the Apple Watch to produce more accurate assessments of your calorific performance) is actually a bit trickier than you might think. We explain how to do this in the next section.

How to use the Apple Watch Activity app: Enter details

Next, you tell the Apple Watch roughly how active you are at the moment. Apple advises you to aim on the low side if you're not sure.

The Apple Watch will take your inputs and use them to generate a (suggested) daily calorie burn goal. But you don't have to accept this; scroll up and down with the Digital Crown to fine-tune your starting goal.

How to use the Apple Watch Activity app: Move goal

Tap the red Start Moving button to complete setup and, well, start moving.

How to use Apple Watch Activity app: How to change your weight or height (or enter details you skipped during setup)

Sadly, if you skip the height or weight section of setup and want to go back and add them (or if your vital statistics change, of course), it's not as simple as opening the Activity app and going to the settings. In fact, you can't even enter the details on the Apple Watch - nor is this accomplished in the Activity app on the iPhone, or even in the Activity section of the Apple Watch app on the iPhone.

You need to go the Health section of the Apple Watch app on the iPhone. No wonder people can't find it.

How to use Apple Watch Activity app: How to change your weight or height (or enter details you skipped during setup)

Open the Apple Watch app on the associated iPhone. From the My Watch tab (the lefthand tab from the options along the bottom of the screen - it should be opened by default), scroll down and select Health. You'll see the four bits of personal information you entered earlier, with 'Not Set' for the ones you skipped.

Tap Edit at the top-right, then tap the entry you want to change. Swipe to the correct value, then tap Done.

How to use the Apple Watch Activity app: How to view your daily targets

Want to see how you're getting on? The Activity app's three rings can be viewed in your glances, so swipe up from your default watch face and swipe sideways until you get to the ring view.

(You can also add the Activity app to your watch's face for even easier access - press down firmly on the watch face, select a face and when customising, choose to add Activity information to the face. This gives you at-a-glance information on your daily targets, and allows you to tap the mini-icon to jump to the Activity app for more detail.)

How to use the Apple Watch Activity app: Face icon

Your daily progress towards these three targets is tracked by three coloured concentric rings: the red outer ring tracks calories burned, the green middle ring tracks exercise, and the blue inner ring tracks standing. (There are also arrow-based icons to help you remember which is which: a single right-facing arrow is calories burned through general movement, the double right-facing arrow is brisk exercise, and the upward-facing arrow indicates standing.)

When the red or green ring completes one circle of the watch face, you've completed that target. The progress of the blue ring is slightly more complicated: it shows the number of hours in which you have stood for at least one minute, out of a target total of 12. We look at each of the rings in a little more detail below.

Scroll upwards using the Digital Crown to see calories, steps and distance covered so far today.

How to use the Apple Watch Activity app: Calories, steps and distance

Alternatively, you can swipe sideways to view individual rings and get more detail on that target.

You can scroll upwards from each ring (using the Digital Crown) to see the activity presented in a graph, by the way.

How to use the Apple Watch Activity app: Graph

Read more Apple Watch tutorials:

How to use Maps on Apple Watch | How to use Siri on Apple Watch | How to use Activity app on Apple Watch | How to reply to a text on Apple Watch | How to answer a phone call on Apple Watch | How to take a screenshot on Apple Watch | How to use Digital Touch on Apple Watch | How to improve the accuracy of the Apple Watch Workout app | How to use the Music app on the Apple Watch | How to use the Apple Watch workout app

How to use the Apple Watch Activity app: The red Move ring

The red Move ring shows the number of calories you've burned so far today via general movement (the large number) and the target for the day (the small number). As with all the rings, the progress of the ring around the watch face shows how close you are to your target: this is the target you set during setup. but you can adjust the target at any time as we explain below.

How to use the Apple Watch Activity app: Red Move ring

How to use the Apple Watch Activity app: How to change the Move goal

As you get fitter and healthier, you'll (probably) want to step up your daily calorie target. The Activity app will suggest new targets automatically each week, but you can manually change the target too.

Go to the red Move ring screen, press firmly on the display and tap Change Move Goal when it appears.

How to use the Apple Watch Activity app: Change Move goal

Scroll up and down with the Digital Crown until you're happy with the new target, then tap Update.

How to use the Apple Watch Activity app: Update Move goal

How to use the Apple Watch Activity app: The green Exercise ring

The green Exercise ring counts up the minutes in which you've been exercising 'briskly', which in practice includes dancing and reasonably strenuous walking as well as formal workouts and runs. The target is 30 minutes per day.

From our experience with the watch, there's a slight delay effect. When walking briskly to the station from home, for instance - a walk of 15 minutes - we were disappointed to find when sitting on the Tube that only seven minutes had been added to the green ring. Yet by the time the train pulled in at the other end it was closer to 20.

We suspect that heartrate monitoring is the issue: logically, it will take a little while to get your heart pumping, so early sections of a period of exercise may not register, yet your heart may take time to get back to normal afterwards. It seems to roughly even itself out.

How to use the Apple Watch Activity app: Green Exercise ring

How to use the Apple Watch Activity app: The blue Stand ring

As explained above, the blue Stand ring is designed to encourage you to sit less and stand up more. You're supposed to stand for a minute each hour, and the blue ring tracks the number of hours in which you've achieved this. The target is 12 hours, each containing at least one minute of standing, per day.

Just standing doesn't always do the trick, though. Many Apple Watch owners have found that a bit of movement is needed to make the device register what you're doing - hop from one foot to the other a few times, or stroll around a little. Go and get a cup of tea.

How to use the Apple Watch Activity app: Blue Stand ring

How to use the Apple Watch Activity app: How to view more information on the iPhone

Remember that you can use the Activity app on the iPhone at any time to get more information about your progress: graphs of your activities over time, for instance, and resting as well as active calories burned. You can also view your achievements ("Perfect week" and so on), if that's something you're into.

Read more: Apple Watch buyers' guide and price list  | How to add and remove Glances on Apple Watch

How to use the Apple Watch Activity app: iPhone app

How to use the Apple Watch Activity app: Wheelchair features

It's been announced (at WWDC 2016) that the Activity app is about to gain some new powers, among them the ability to track your movements if you're in a wheelchair. This is all part of the upcoming watchOS 3 update, which is expected in the autumn.

We discuss watchOS 3's wheelchair-focused features - as well as rival fitness trackers that are suitable for users with disabilities - in a separate article: Best fitness & activity trackers for wheelchair users.

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