Wednesday, October 2, 2019
Heart rate monitors
Since we are learning about heart rate max and heart rate training zones, I am curious what your thoughts are about the accuracy of heart rate monitors, heart rate monitors on exercise machines, fit bit, phones and Apple Watches. The assignment is to find 2 articles about this topic and write a short synopsis and personal opinion about heart rate monitors accuracy. Please post below in the comments section and include the links to your articles your researched.
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https://www.tomsguide.com/us/heart-rate-monitor,review-2885.html
ReplyDeletehttps://www.health.harvard.edu/staying-healthy/rating-heart-monitors
From what I have read in these articles, I found the Polar Chest Strap is the best for monitoring heart rate, but not by much. The Apple Watch and the Samsung Galaxy Watch only took a couple seconds to catch up to the chest strap. By the chart in the first link, they are all very accurate and all have very similar results. In the second article I read, they talked about another chest strap with four different activity monitors. With four monitors, the strap will be 99.6% accurate. The chest strap was not named but with only one monitor it could’ve been just 83% - 91% correct and could be off up to 15 beats per minute to 34 beats per minute. If you want to stay as accurate as possible, they say to choose the chest strap.
https://docs.google.com/document/d/1H6lqwXhw9DzjzPaiS3RrDIDNaFNQ8iME2adH3_AYMco/edit
ReplyDeleteUsing the chest strap was almost as accurate as an EKG at 99% accuracy. THen the apple watch came in 2nd at 93% accuracy. I think that the chest strap would be good for people that need to keep track of their heart rate for medical purposes, and people could use the apple watch when they are working out. I think that the Apple watch is accurate because people using them are just curious to know how fast their heart is beating. I think this is accurate because from the article that I read, it says that Apple watches are 93% accurate.
ReplyDeletehttps://www.businessinsider.com/the-apple-watch-has-the-most-accurate-heart-rate-monitor-according-to-new-research-2016-10
In another article that I read, It states that every smartwatch or band had to go through the FDA and make sure that ir reliable. The optical heart-rate sensor found in most fitness trackers and smartwatches today uses photoplethysmography (PPG). PPG projects a green light on the skin. The light that isn't absorbed by the tissue beneath the skin is reflected back to the sensor, which then measures the variations to calculate your heart rate. The FDA has to check and make sure that the PPG is accurately put together and it works the right way. The chest worn devices use electrodes to measure your pulse which is more accurate than PPG. As I kept reading, It says that serious athletes should use the chest worn strap, but they prefer them to wear the smart watches because over time they become accurate. It also states that the chest straps cant send you notifications to lead you through breathing exercises, measure sleep, or measure stress. In my opinion I would rather train with a smartwatch because it helps with leading in breathing exercises and it measures the same as the chest strap it just take a second to get accurate.
https://www.tomsguide.com/us/heart-rate-monitor,review-2885.html
https://docs.google.com/document/d/1D2ES2NxuEP6M336PVTz5r7Wjgj0V4vrNDOEb3EOU1aQ/edit?usp=sharing
ReplyDeleteHeart rate monitors are devices that calculate how many times your heart beats per minute. Which is the most accurate? Studies show that chest strap monitors are the most accurate. According to Life Science, “In general, the wrist-worn monitors were most accurate when the person was at rest, and their accuracy diminished as the wearer's activity level increased, the researchers said.” Dr. Marc Gillinov, a cardiac surgeon at the Cleveland Clinic, claims that it is too early to use wrist heart rate tracking devices to diagnose to guide therapy for heart disease patients. The studies on wrist-worn heart rate monitors is limited to just running on a treadmill as of now. In the future they hope to test the monitors when people are swimming, biking, and doing other forms of exercise. Several companies have come out and stated that their watches are not intended to be used as medical devices. “In a statement, Fitbit said that its trackers are not intended to be medical devices. The company's own tests showed that their heart rate monitor "performs to industry standard expectations" for optical heart rate monitoring on the wrist, and has an error of less than 6 bpm, on average, when compared to a chest strap.” The way a wrist-worn heart monitor works is that They shine a light into the blood vessels in your wrist, and then detect the changes in blood volume that occur each time your heart beats and pushes blood through your body. This can be not accurate when you are working out because of how much you move around. Because you are moving around, it is difficult for the watch to accurately shine the light in the blood vessels and get an accurate reading.
ReplyDeletehttps://www.livescience.com/56459-fitness-tracker-heart-rate-monitors-accuracy.html
https://www.acc.org/about-acc/press-releases/2017/03/08/14/02/wrist-worn-heart-rate-monitors-less-accurate-than-standard-chest-strap
I think that the exercise equipment is pretty accurate to an extent. In 13 abc’s news article they said that they put a heart monitor strap on a girl and got her heart rate. Then they put her on the one in the gym and it was either 1 beat up or down. Now for detecting other things on a heart monitor on the equipment might not be as accurate, but there are different factors that could affect the reading. Some of those factors are, movement, what type and even sweat. The samsung chest strap is about 99% accurate, almost as accurate as the EKG. The apple watch is only about 91% accurate. A doctor at the Cleveland Clinic said that the watches or the wrist based bands might bounce or come up and not detect everything and lose some of that contact. Out of all the wrist heart monitors the apple watch is the most accurate.
ReplyDeletehttps://www.businessinsider.com/the-apple-watch-has-the-most-accurate-heart-rate-monitor-according-to-new-research-2016-10
https://abcnews.go.com/Health/accuracy-exercise-machines/story?id=18559149
https://woman.thenest.com/accurate-heart-rate-counter-treadmill-16519.html
Compared to a Fit Bit, this measurement for this device is super accurate. They tested the apple watch on about 2,000 people and were 91% accurate. Which for the size of the device 91% is a great number. The only reason it isn’t 100% because when the device leaves your wrist and stop touching for even .3 seconds it will glitch it.
ReplyDeletehttps://www.businessinsider.com/the-apple-watch-has-the-most-accurate-heart-rate-monitor-according-to-new-research-2016-10
The Fit Bit Charge 3, which currently has the best heart rate for all Fit bits, only have 84% accuracy. A fitbit is about half the size of an Apple watch. This device is super accurate and measures the best when your heart rate is resting. As the amount of activity goes up the more random answers or more variables pop up. Even though they both accurate i would have to say the apple watch is better.
https://www.businessinsider.com/the-apple-watch-has-the-most-accurate-heart-rate-monitor-according-to-new-research-2016-10
So far in this article they have been talking about this chest monitor called the Polar H10. They did some tests on different heart rate monitors and the Polar H10 was the best one, but not by far. The apple watch and the Samsung's Galaxy Watch took seconds to catch up to the Polar H10. The fitbit versa isn’t the best heart rate monitor because if they don’t fit your wrist properly then that could change or mess up your bpm. Most of the heart rate monitors they tested were inaccurate and all over the map but some of the watches were really close to the Polar H10. Lastly, the Polar H10 was 99% accurate than the other heart rate devices.
ReplyDeletehttps://www.tomsguide.com/us/heart-rate-monitor,review-2885.html
The Fit bit watches are not as accurate as most people think they are. They did testing on different models of the fitbit and they were less accurate during an exercise than at rest. These monitors could be over 39 beats per min off. Some of the researchers say these wrist heart rate monitors are less accurate because they could move around during an exercise and hen it won’t get the correct bpm. The fitbit watch is better for those who want some feedback to help them increase their exercise level, researchers said.
https://www.cbsnews.com/news/fitness-tracker-heart-rate-accuracy-study-fluctuations/
I believe that the apple watch in particular is pretty accurate. I own one myself, and it’s pretty accurate. Apple claims the technology isn’t perfect, but it does an excellent job. It is already accurate on it’s own, but there are things the user can do to make the watch more accurate. The first is to clean the sensor. Speaking from experience, sweat from my hands and wrists dries on the sensor and it forms a layer on top. Keeping the sensor clean can help that, as well as wearing a rubber case on the watch to prevent the watch from slipping. Not every heart monitoring device is 100% accurate. The Wall Street journal claims that the apple watch is not as accurate as the chest monitor, which is true. But when tested, the watch did better than the Journal claimed. “After about a month of regular heart rate monitoring, my results matched the Wall Street Journal. The variance wasn’t as extreme as they found. My results varied by about 10%. Rarely, my results were just crazy. One time my heart rate was 250! Wow, I must be a Timelord with two hearts! To be fair, when I had an EKG test, they once had to do it over. All monitoring devices can mess up.” (groovypost.com article)
ReplyDeletehttps://www.groovypost.com/unplugged/apple-watch-accuracy-heart-monitoring/
I believe that heart rate monitors on exercise machines can be accurate, but are not preferred over chest mounted or wrist mounted monitors. A broken clock is right twice a day. I believe that they are not consistent enough to be reliable. It is hard to hold onto handles on a treadmill while running, which makes it harder to get a good reading. There are too many factors that can affect the reading you get from an exercise machine heart rate reading, so it makes more sense to wear a chest monitor or a wrist monitor.
https://woman.thenest.com/accurate-heart-rate-counter-treadmill-16519.html
The Wall Street Journal did an experiment by using the results from the Apple Watch heart monitor and a Whoo chest monitor. While doing interval training on the treadmill, the two results of the devices were compared. The results varied by 10%, but overall both were extremely close. For an Apple watch, some variables come into play and things can be done to receive more reliable results. Keeping the watch clean of sweat and wearing a case can increase your chances of accuracy. Bluetooth now allows Apple watches to be connected to chest monitor, so results on both ends will end up being the same numbers. https://www.groovypost.com/howto/create-virtual-machine-windows-10-hyper-v/
ReplyDeleteCBS reveals that the Apple watch was one of the most accurate heart monitors in treadmill tests. Fitbits were proven to not be as accurate as of the watch, by having numbers far from the on the chest monitor. The Clevland Clinic’s findings show that reading from the Fitbit or chest monitor was off by 30 or 40 bpm. Patel says that watch devices can give a general sense of heart rate patterns. Advanced devices such as the chest monitor should be used to be reliable for series clinical care. For example, cardiac patients should be using a chest monitor to hit their target heart rate, so they know that results are the most accurate they can be. https://www.cbsnews.com/news/fitbit-apple-watch-heart-monitors-accuracy-tests/
In conclusion, I believe Apple watches are a great tool just to see a reference to what your heart rate is while working out. I wouldn't trust it 100%, but studies show it is pretty close. Professional athletes or people that are more series about knowing their bpm on the dot should use a chest monitor. Then they know things like sweat or not wearing a case on their watch will not alter their results. Also, people that have health conditions should also use the chest monitor so they have the best results for their health.
https://docs.google.com/document/d/1esRpTjDYLFuV2aFNejs464mNLK1-SDfQE5fnenVfFY0/edit?usp=sharing
ReplyDeleteHeart rate monitors that are accessories are good little tools to have, but if you truly need a good reading of your heart rate they are not always accurate. If you are using a monitor for medical use, apple watches and fitbits aren’t the answer. The world's largest database, Clinical Trials, revealed that nearly 200 trials involving fitbit and concluding that it isn’t even in the range of being a medical device. Fitbit claims its used for recreational purposes not medical. The way the fitbit works is it takes the measurement of artery volume using light. It is very hard to get a good read because your heart rate signals and motion interference overlap so much. That is why Fitbit has a 27% margin of error. Fitbit encourages you to read your fitbit at times where motion is less existent, but thats when people are most curious. I think fitbits and apple watches are cool and nice to have, but don’t always trust your watch. Heart rate monitors on your treadmill is cool to have and can help gage your cardiovascular intensity, but they aren’t 100% either. Treadmills, ellipticals, etc have proven to over or underestimate your heart rate by 15-20%. However, all of these tools are not 100% accurate, I think they are convenient to have as a guide in the gym.
ReplyDeletehttps://www.independent.co.uk/life-style/health-and-families/health-news/heart-rate-monitor-unreliable-fitbit-garmin-health-science-technology-a8413196.html
https://help.fitbit.com/articles/en_US/Help_article/1136
Heart rate monitors like the ones at your doctor are great and accurate, while the apps that monitor your blood pressure may not be as accurate. Consumers have been warned to not focus on what mobile apps say is your blood pressure because there is no law on these apps requiring validation and accuracy tests. The first website explains how they compared tests of an ECG and the 4 apps that were supposedly the best and they found differences up to 20 bpm in 20% of test and some apps performed worse. Non-contact apps often perform worse than apps with contact to the phone, making sense because all you have to do on those apps is look at the camera. There are some apps with contact that ultimately perform excellently and accurately but it may be inconsistent as that was not tested. Therefore, getting heart rate tested based on apps and technological advances in iphones may be more convenient but also could be less accurate and give you false information that can lead you thinking you have something wrong.
ReplyDeletehttps://www.escardio.org/The-ESC/Press-Office/Press-releases/consumers-warned-about-accuracy-of-heart-rate-apps
https://www.sciencedaily.com/releases/2017/05/170503092146.htm
I believe that wrist worn heart-rate monitors are not particularly accurate. The makers of these products state that they are not intended for medical purposes and not supposed to match other medical devices. Studies show that chest strap monitors are more accurate than wrist worn heart-rate monitors. Some smart watches, like the Apple Watch, tells you if your heart rate is too high or too low when not exercising, which can help prevent serious health issues. Watches could also be inaccurate if they do not fit your wrist well. Apple Watches have been tested to be about 1-3 bpm off of a chest strap monitor while running and almost perfect when resting and walking. The Garmin devices have shown to be the most accurate when tracking heart rates during workouts. If you are serious about tracking your heart rate, you may want to go with the chest strap monitor, as it is proved to be the most accurate. Watches, however, are still good to use if you want to know your approximate heart rate.
ReplyDeletehttps://www.independent.co.uk/life-style/health-and-families/health-news/heart-rate-monitor-unreliable-fitbit-garmin-health-science-technology-a8413196.html
https://www.tomsguide.com/us/heart-rate-monitor,review-2885.html
https://docs.google.com/document/d/1KI6X9Jl4_sT-MI-Z6xKa_CKFO3c6CbO8XbwnJt2bCr8/edit
ReplyDeletehttps://docs.google.com/document/d/1FPlICx7Rpw1RfNlrM4jflVsBvrClNZfdemfyrVATXgg/edit
ReplyDeleteAfter reading about and looking into the topic, I dont think that the smart device heart rate monitors are very accurate. A study conducted by Dr. Christophe Wyss, a cardiologist at Heart clinic Zurich in Switzerland, tested the accuracy of four different commercially apporived heart rate monitor apps. The study included 108 patients who had their heart rate measured by ECG, pulse oximetry, and each app using each phone. The test results showed major differences between all four of the apps. In some of the apps there was a difference of more than twetny beats per minute compared to the ECG. Only one app was “approved” to being accurate. That was one of the contact apps on the iphone. The app was called excellent by Dr Wyss. Another study published Wednesday in JAMA Cardiology, tested the Apple Watch, Fitbit Charge HR, Basis Peak and Mio Alpha wristbands. In the end, the apple watch and the mio fuse did the best. They tested with about 90% accuracy. All the others tested with about or below 80%. However something like having dark skin or a dark tattoo over you wrist can easily affect the performance of the iphone. I did not expect any of them to be 100% accurate at all. So I think that using a heart rate monitor app is not the best choice if you want a very accurate number. However; If you only need a rough estimate number I think it would be a good choice to use, If you use one of the more accurate ones like the iphone.
ReplyDeletehttps://www.sciencedaily.com/releases/2017/05/170503092146.htm
https://www.npr.org/sections/health-shots/2016/10/15/497828894/you-can-monitor-your-heart-with-a-smartphone-but-should-you
Some personal heart rate monitors such as are not the most accurate tool, but not all are bad. For the built in monitors on watches and phones numbers seem to vary from product and producers. Dr. Christophe Wyss tested 4 apps from 2 different iPhones, the iPhone 4 and 5. Over the 108 people tested there was wide variety between the apps. Each subject had their heart rate taken by an electrocardiogram (ECG) and an app from each phone. Differences of more than 20 beats per minute ranged from the apps in over 20% of the measurements.
ReplyDeleteIn comparison, a similar test was run with four smart watches. The experiment started with the subjects getting an ECG after walking on a treadmill. After their heart rate had decreased they were asked to do it again this time with either and Apple watch, Fitbit Charge, Mio Fuse and Basis Peak. The top performances were given by the Apple Watch and Mio Fuse; most of the results ranging in 29 beats under to 27 beats over. While the others ranged from 39 beats under and 34 beats over. EKG, which are portable heart rate monitors that you strap to your chest, are still the most accurate as they can detect the contraction of the heart since they are so close. I think an EKG and ECG are the most accurate tools to use, but for convenience one of the higher ranked smart watches are acceptable.
https://www.escardio.org/The-ESC/Press-Office/Press-releases/consumers-warned-about-accuracy-of-heart-rate-apps
https://www.livescience.com/56459-fitness-tracker-heart-rate-monitors-accuracy.html
Today, there are many devices that can track your heart rate by the tip of your fingers. One of the most popular devices is the apple watch. The apple watch has many functions, but few years ago, apple announced that the watch has the ability to track heart rate. However how accurate are these devices when it comes to tracking heart rate? Caiitlin McGarry had the same question in her article Who Has the Most Accurate Heart Rate Monitor. Her team compared the results from the apple watch to a chest-strap reading, and results were almost exactly the same. However there are some things that can come into effect with taking someone’ s heart rate with these devices. In my opinion, I think the apple watch is a great and efficient way to check your heart rate while doing physical activity. Although in some cases readings will not be completely accurate, the apple watch is still a great tool to use when checking your heart rate. With all these new devices coming out, people will have easy access to monitoring their health.
ReplyDeletehttps://www.tomsguide.com/us/heart-rate-monitor,review-2885.html
https://www.businessinsider.com/the-apple-watch-has-the-most-accurate-heart-rate-monitor-according-to-new-research-2016-10
The chest strap is one of the most accurate heart rate monitors but it does not send you notifications, help you with breathing exercises or measure stress. Apple watch series 4 is said to have the most accurate heart rate monitor. If and only if it is placed properly on your wrist. When the watch does not fit snug on your wrist it could alter the accuracy of the device. It sits on you wrist all day making it very easy to get the most accurate heart rate and other readings. The watches have to be checked through the US Food and Drug Administration. The tests taken between a chest strap and the Apple Watch were very similar only varying between 1-2 numbers. There are other devices that read your heart rate one is the machines at gyms but they are not accurate because they only take factors about your pace and weight. They do not take the factors of your metabolism or body type. "The best it can do is give you an estimate based on generalities," said exercise physiologist Polly de Mille.
ReplyDeletehttps://abcnews.go.com/Health/accuracy-exercise-machines/story?id=18559149
https://www.tomsguide.com/us/heart-rate-monitor,review-2885.html
In today’s society, people rely on technology for many things, including fitness tracking. Many watches, apps, and machines exist to track heart rates, even though they are not always accurate. Dr. Christophe Wyss, a cardiologist in Switzerland said, “The problem is that there is no law requiring validation of there apps and therefore no way for consumers to know if the results are accurate.” He conducted a study to find the accuracy of these apps by comparing their data to the standard clinical measurement. His data showed that most apps were inaccurate and untrustworthy. A similar study was held by JAMA Cardiology to test the different types of fitness watches. 50 healthy adults wore two of four types of fitness watches, and also wore a chest strap monitor to have a benchmark to compare the watch accuracy. The results, similar to the first study, showed that the fitness watches had inaccurate and unreliable heart rate monitors.
ReplyDeletehttps://www.sciencedaily.com/releases/2017/05/170503092146.htm
https://jamanetwork.com/journals/jamacardiology/article-abstract/2566167
https://tinyurl.com/y3rsgo2y
ReplyDeleteNick Hills
ReplyDeleteApple is the most accurate watch for measuring heart rate, with 94% accuracy. Other brands are good but they only had 80% accuracy. The chest straps are still more accurate though, getting 99% accuracy. Watches lose accuracy as the work intensity increases, because they lose contact with the wrist and that causes them to read the heart rate wrong. If measuring heart rate is very important to you, it is recommended to get a chest strap monitor as they are more accurate. Watch heart rate monitors use light to measure your heart rate. They use light to detect and measure changes in your blood volume everytime your heart pumps.
I think wrist heart monitors are really good depending on what brand you have. They are more convenient, since you don’t have to put on a big chest strap that is uncomfortable to workout in, and you don’t have to hook up patches to measure your heart rate. Watches are quick and they are accurate enough to look at after a workout to know your heart rate. They are very small and most people have a watch on anyways, so it is better for people who just want to check it and keep working out. Most of them also track distance when running, they can track calories burned, and time your runs. They are great for working out for this reason, especially when running for long distances.
https://www.businessinsider.com/the-apple-watch-has-the-most-accurate-heart-rate-monitor-according-to-new-research-2016-10
https://www.livescience.com/56459-fitness-tracker-heart-rate-monitors-accuracy.html
The most accurate monitor is the chest strap. The wrist watches were pretty accurate but the chest strap was more accurate. Wrist-worn trackers use optical sensors that detect light bouncing back from blood flowing beneath the skin, and then measures your pulse. Chest straps meeasure the heart’s electrical activity with electrodes. There have been more tests on chest-strap monitors and not as many of wrist-worn. 50 healthy adults walked on a treadmill, from 2mph to 6mph, and wore a wrist tracker on each wrist. They also wore an H7 chest-strap from Polar. The chest-strap measurements were almost all identical but the wrist monitors weren’t as accurate.
ReplyDeletehttps://www.livescience.com/56459-fitness-tracker-heart-rate-monitors-accuracy.html
The fitbit and Garmin watch both state that they aren’t for medical purposes, just for recreational use and that their heart rate reading aren’t always going to be accurate. Fitbit had a lawsuit held against them because a person in california said their heart rate monitor was “grossly inaccurate and frequently fail to record any heart rate at all”. The amount of reflected light depends on the volume of arteries near the skin’s surface. Blood in the arteries absorbs light better than the surrounding body tissues, as the arteries contract and swell in response to the pulse, the reflected light will rise and fall. This allows for the watch to not be the most accurate monitor to use.
https://www.independent.co.uk/life-style/health-and-families/health-news/heart-rate-monitor-unreliable-fitbit-garmin-health-science-technology-a8413196.html
During a study, some of the wrist-worn monitors weren’t as accurate as others but the chest-strap was the most accurate of them all. Dr. Marc Gillinov said that if you want an accurate measure then you should get the chest strap, with an electrode, instead of a wrist monitor. There hasn’t been as much study done on wrist worn watches compared to the chest strap.
https://www.livescience.com/56459-fitness-tracker-heart-rate-monitors-accuracy.html
Apple Watch has the most accurate heart-rate monitor according to new research. Apple Watch heart rate sensor. Apple Measuring heart rate accurately is pretty easy, comparatively speaking. In all, they recorded 1,773 heart-rate readings across all the devices, with readings ranging from between 49 and 200bpm. https://www.businessinsider.com/the-apple-watch-has-the-most-accurate-heart-rate-monitor-according-to-new-research-2016-10
ReplyDeleteI found Garmin devices, including the Forerunner 35 and the Fenix 5, accurately tracked the heart rate during workouts, but were all over the map when resting or walking outside of a workout. A walk wearing the Polar H10 chest strap and the Forerunner on my wrist, and you noticed the Forerunner's heart rate jumping from the 140s down to 120s and then to the 90s, where the H10 steadily reported a walking heart rate in the high 90s.
https://www.tomsguide.com/us/heart-rate-monitor,review-2885.html
The best thing to monitor your heart would be the Garmin devices because they semi accurately tell you heart rate better than an apple watch or anything else would.
Apple Watch has the most accurate heart-rate monitor according to new research. Apple Watch heart rate sensor. Apple Measuring heart rate accurately is pretty easy, comparatively speaking. In all, they recorded 1,773 heart-rate readings across all the devices, with readings ranging from between 49 and 200bpm. https://www.businessinsider.com/the-apple-watch-has-the-most-accurate-heart-rate-monitor-according-to-new-research-2016-10
ReplyDeleteI found Garmin devices, including the Forerunner 35 and the Fenix 5, accurately tracked the heart rate during workouts, but were all over the map when resting or walking outside of a workout. A walk wearing the Polar H10 chest strap and the Forerunner on my wrist, and you noticed the Forerunner's heart rate jumping from the 140s down to 120s and then to the 90s, where the H10 steadily reported a walking heart rate in the high 90s.
https://www.tomsguide.com/us/heart-rate-monitor,review-2885.html
The best thing to monitor your heart would be the Garmin devices because they semi accurately tell you heart rate better than an apple watch or anything else would. - Anastasia Weekley
Nick Kesler
ReplyDeletehttps://www.health.harvard.edu/staying-healthy/rating-heart-monitors
https://www.tomsguide.com/us/heart-rate-monitor,review-2885.html
From reading the articles I found that heart rate monitors are accurate but some are better than others. It depends on how the monitor fits but the machines are always advancing. Toms guide states that the polar chest monitors are the most accurate when it comes to reading heart rate. Although the wrist monitors lagged behind the chest monitors with time and a few beats away from each other. Apple watches are one of the more reliable wrist heart monitors. From tests they have done the apple watch is only .6 overall variance in heart rate from chest monitors from doing study's of walking and running. Study's show that fit bits are one of the worse brands to choose from about heart rate. In my opinion heart monitors are not always accurate because every fit tells a completely different heart rate. With the information I read I dont think technology is completely there yet.