Apple Watch features a heart rate monitor to help guide you through your workout sessions, tracking your heart rate while you exercise to better determine the amount of calories you burn during your activities.

The monitor also automatically tries to measure your heart rate every 10 minutes, but doesn’t record the data if your arm is moving. That is why your Health app doesn't reflect a reading at every 10 minutes on the dot, but shows varying intervals of readings.

Apple Watch Heart Rate Monitor 1
If you want to get a quick, accurate measurement of your heart rate manually you can do so in Glances.

The heart rate sensor is on the backside of the Apple Watch case and is made up of two different sets of special lights that monitor the blood flow through your wrist. Because the sensors absorb light through your skin, there are a few factors that affect the accuracy of a heart rate reading.

Apple Watch Heart Rate Sensor 2
By following a few tips, as well as calibrating Apple Watch for workouts, you will get a better heart rate reading, thus improving the device's ability to more determine how many calories you burn.

A Proper Fit

As simple as it sounds, a good fit is key to getting an accurate heart rate reading. Some people don't like the way it feels to have their watch snug on their wrist, but for the purposes of a proper reading, you'll need to keep it tight. When you hold your wrist out, there should be no gap between Apple Watch and your skin.

Apple Watch Correct Fit
If the feeling is just too uncomfortable for you to wear the device snug to your wrist, it might be a good idea to adjust the band differently for different activities. If you are working out, tighten it up one notch until you are done.

Avoid Cold Weather Workouts

The heart rate sensor is affected by how much blood flows through your skin. In cold weather, we tend to produce less blood flow near the surface of the skin as the blood is rerouted to warm more important parts of our bodies (it is why our fingers and noses get so cold). Some people enjoy jogging in the snow, but keep in mind that this may have an affect on an accurate heart rate reading from your Apple Watch.

Avoid Irregular Motion

Apple Watch gets a better reading when you've calibrated it by walking or running for 20 minutes. It tracks the rhythm of your movement and adjusts its data accordingly.

However, irregular movement, like playing tennis or boxing, will confuse the sensor and reduce its accuracy. So, for such workouts that have you swinging your arms wildly, be aware that your heart rate reading may not be as accurate as you would like.

Troubleshooting

If, for some reason, the heart rate monitor on your Apple Watch stops working, you may need to restart or reset the device.

Apple Watch Erase All Settings

  1. Press and hold the Side button until the power off slider bar appears and slide it to turn off Apple Watch.
  2. Press and hold the Side button again until the Apple Watch logo appears.

If that does not work, try resetting your Apple Watch.

  1. On Apple Watch, open the Settings app and tap General.
  2. Tap Reset. Then tap "Erase All Content and Settings."
  3. Re-pair Apple Watch with your iPhone.

Although it is not an exact science, the heart rate monitor on Apple Watch is a useful way of tracking your activities and getting a better estimate on how many calories you burn. Following the tips above will improve accuracy of the light-absorbing sensors.

Related Roundup: Apple Watch Series 6
Buyer's Guide: Apple Watch (Neutral)

Top Rated Comments

Iconoclysm Avatar
76 months ago
That gap/no gap method is incorrect as this differs greatly depending on the shape of your wrist. If the watch is snug, it's snug, if it can't move around...it can't move around. For some people, that will mean there is a gap in the band. The watch itself is raised up, if you have a slimmer wrist, it is absolutely impossible to remove that gap.
Score: 6 Votes (Like | Disagree)
0098386 Avatar
76 months ago
Step 1) don't have a sleeve tattoo.
Score: 4 Votes (Like | Disagree)
Zakkates Avatar
76 months ago
The heart rate monitor is pretty much useless when I'm lifting weights (especially HIIT).

When I'm on the treadmill at a steady pace, the Apple Watch most often is spot on with what the machine says my heart rate is.

However, when I'm lifting weights w/ a lot of movement, I can feel my heart rate is at least over 150bpm, but the Apple Watch freaks out and says I have "37bpm" or "87bpm" or can't read. It's very frustrating.

Does hair on the wrist effect it at all?
Score: 1 Votes (Like | Disagree)
nick42983 Avatar
73 months ago
The heart rate monitor is pretty much useless when I'm lifting weights (especially HIIT).

When I'm on the treadmill at a steady pace, the Apple Watch most often is spot on with what the machine says my heart rate is.

However, when I'm lifting weights w/ a lot of movement, I can feel my heart rate is at least over 150bpm, but the Apple Watch freaks out and says I have "37bpm" or "87bpm" or can't read. It's very frustrating.

Does hair on the wrist effect it at all?
I've had the same problems with weightlifing. Sometimes I'll simply exit out of the workout app and go to the HR monitor in glances until it gets the right reading and then go back to the workout app and it will update with the proper measurement. When it's accurate it's great, but I feel that 30%+ of my gym calories burned aren't being measured.
Score: 1 Votes (Like | Disagree)

Top Stories

siir apple event april 20

Siri Reveals Apple Event Planned for Tuesday, April 20

Tuesday April 13, 2021 12:04 am PDT by
Siri has apparently prematurely revealed that Apple plans to hold an event on Tuesday, April 20, where the company is expected to reveal brand new iPad Pro models and possibly its long-awaited AirTags trackers. Subscribe to the MacRumors YouTube channel for more videos. Upon being asked "When is the next Apple Event," Siri is currently responding with, "The special event is on Tuesday, April...
apple event spring loaded

Apple's 'Spring Loaded' Event Officially Announced for Tuesday, April 20

Tuesday April 13, 2021 9:04 am PDT by
Following an overnight leak by Siri, Apple today officially announced that it will be holding a special "Spring Loaded" event on Tuesday, April 20 at 10:00 a.m. Pacific Time at the Steve Jobs Theater on the Apple Park campus in Cupertino, California. As with all of Apple's 2020 events, the April 2021 event will be a digital-only gathering with no members of the media invited to attend in...
pixel watch prosser leak

Google Pixel Watch Allegedly Leaks with Circular Design, Rumored to Launch in October

Monday April 12, 2021 2:49 am PDT by
Renders of Google's first smartwatch, codenamed "Rohan," have been shared by Jon Prosser, showing that Google plans to adopt a circular design for its flagship wearable watch. Prosser shared the renders in an episode of his YouTube show "Front Page Tech," in which he claims they were made based on marketing material he had seen from a source within Google. The renders show that the Pixel...
Google maps feaure green

Google Maps App for iOS Finally Updated After Four Months

Monday April 12, 2021 10:03 am PDT by
Following the completed rollout of App Privacy labels for its App Store apps, Google today updated the Google Maps app for the first time in four months. Apple in December began requiring all new app submissions and app updates to include App Privacy labels, detailing the data that is collected by the app so consumers know what they're sharing. Google didn't begin implementing App Privacy ...
AppleTV and HomePod Feature

Bloomberg: Apple Working on New Apple TV With Integrated HomePod Speaker and FaceTime Camera

Monday April 12, 2021 3:32 am PDT by
Apple is working on a combined Apple TV with HomePod speaker that has a camera for video calls through a connected television set, according to Bloomberg's Mark Gurman. From the report: The company is working on a product that would combine an Apple TV set-top box with a HomePod speaker and include a camera for video conferencing through a connected TV and other smart-home functions,...
samsung experience 1

Samsung's 'iTest' Lets You Try a Galaxy Device on Your iPhone

Thursday April 8, 2021 12:42 pm PDT by
Samsung has launched "iTest," an interactive website experience that's designed to allow iPhone users to test out Android on a Galaxy device, or "sample the other side," as Samsung puts it. Subscribe to the MacRumors YouTube channel for more videos. The iTest website is being advertised in New Zealand, according to a MacRumors reader who came across the feature. Visiting the iTest website on...
epic iap feature 3

Tim Cook Says App Store Would Become a 'Flea Market' if Third-Party Payment Systems Were Allowed

Monday April 12, 2021 9:41 am PDT by
In a recent interview with the Toronto Star, Apple CEO Tim Cook spoke about a wide variety of topics, ranging from App Tracking Transparency to Apple's ongoing legal battle over App Store policies with Fortnite creator Epic Games. Notably, Cook said that Epic Games' desire for Apple to let developers offer their own payment systems in apps "would make the App Store a flea market":At the...
tim cook toronto star

Tim Cook Says Apple is 'Not Against Digital Advertising' Ahead of iOS 14.5 Launch With App Tracking Transparency

Monday April 12, 2021 8:00 am PDT by
Starting with iOS 14.5, iPadOS 14.5, and tvOS 14.5, Apple will be requiring apps to receive a user's permission to track their activity for targeted advertising purposes, as part of a privacy measure known as App Tracking Transparency. Ahead of App Tracking Transparency being enforced, Apple CEO Tim Cook has participated in a privacy-focused interview with the Toronto Star, telling the...
a13 bionic mockup

Apple Made Sudden Security Changes to its Chips in Fall 2020

Monday April 12, 2021 8:15 am PDT by
Apple made unusual mid-production hardware changes to the A12, A13, and S5 processors in its devices in the fall of 2020 to update the Secure Storage Component, according to Apple Support documents. According to an Apple Support page, spotted by Twitter user Andrew Pantyukhin, Apple changed the Secure Enclave in a number of products in the fall of 2020:Note: A12, A13, S4, and S5 products...
HomePod G4 Feature

Bloomberg: Future HomePod May Feature iPad Connected Via Robotic Arm to Track Users Around The Room During FaceTime Calls

Monday April 12, 2021 3:50 am PDT by
In a report outlining a possible Apple TV with a combined HomePod and camera, Bloomberg's Mark Gurman says that Apple is exploring a future high-end HomePod speaker that could include an iPad connected via a robotic arm that tracks and follows users around a room. From the report: The Cupertino, California-based technology giant, is also mulling the launch of a high-end speaker with a touch ...