Yesterday I got a chance to test out the GPS and heart rate sensor on the new Fossil Sport Smartwatch. Before purchasing the watch I’d read and watched several reviews but none of them covered the “sport” aspect of the watch. Is the GPS any good? Is the heart rate sensor on the Fossil Sport accurate? Well, my first test outdoors with the watch came back very good!

Update: I’ve also tested both against a chest heart rate monitor, the Polar H10, which you can pick up on Amazon, for an indoor workout and those results are now below.

The Fossil Sport is a Wear OS smartwatch with all the bells and whistles that a smartwatch can come with. It has Google Pay, Google Assistant, Google Maps, the latest chip, is waterproof for swimming, and comes in a variety of colors and styles to suit just about anyone.

Heart Rate Accuracy

I had already tested out the heart rate sensor on the Fossil Sport in the gym and it did well. There’s still more testing to do for different types of activities but on the treadmill it did great and usually if a watch does good in my first test on the treadmill with walking/running, it’s probably going to test out well from there on out. I can tell very quickly how good a heart rate sensor is.

The Vivoactive 3 Music’s heart rate sensor performed well on the treadmill but not as good as the Fossil Sport. I’d compared them against each other on the treadmill too and the Fossil did better.

In my outdoor test, the Fossil Sport blew the Vivoactive 3 Music away in terms of heart rate sensor performance. I was surprised!



Hopefully, it was just a fluke for the Vivoactive but it consistently estimated my heart rate in the 90s as I was walking rather briskly on a blustery day in a park.

Having tested several other watches in the same park on the same route, I pretty much know what’s a normal range for my heart rate during certain activities. I would expect my heart rate to be in the 115-120 bpm range if I’m walking quickly. At one point, I purposely walked fast up a hill and the highest the Garmin showed my heart rate as was 104 bpm which I know is too low based upon other tests.

At the end of the walk, the Fossil Sport showed a max heart rate of 129 bpm and an average of 118 bpm. The Vivoactive 3 Music showed a max of 108 bpm and an average of 97 bpm. That’s a big difference.

The Fossil Sport may have overestimated here and there but I’ll be comparing both watches versus a chest heart rate strap and I’ll share those results here. I want to do this same route again and see which one truly comes ahead and I’ll update this article with that new data.

The heart rate graph on the Fossil Sport after finishing.

Google Fit vs Garmin

I think it’s important to also understand how these two watches approach fitness. They are similar in many respects but there are differences.

The Fossil Sport of course uses Google Fit which focuses on what Google calls move minutes and heart points. As you can see from the image below I earned 23 move minutes and 20 heart points at that point of the day. The daily goal by default is 60 move minutes and 10 heart points. It also shows the total amount of calories I’ve burned throughout the day and the number of steps.



Google Fit works similar to the Apple Watch. Instead of focusing on steps like Fitbit and many other fitness trackers do, Google Fit and Apple focus more on active minutes but Google Fit also focuses on cardio fitness with the heart points.

Garmin Vivoactive 3 Music
Garmin Vivoactive 3 Music | View Price and Availability on Amazon

Garmin focuses on steps but also what it calls intensity minutes and I like this a lot about Garmin. It gives me a good breakdown on the watch and through the mobile app of not only the day but the week. Garmin suggests 150 weekly intensity minutes. These are minutes when you’re getting your heart rate up and giving it a good workout. I like that I can focus on the week instead of just one day so if I don’t do so great one day, I can do better the next and still get my weekly intensity minutes in.

Google Fit also gives a weekly breakdown of your move minutes and heart points which I think is helpful if you’re trying to become more physically fit and see how active you are throughout the week and make adjustments if necessary.

It’s probably better to focus more on physical activity that improves the cardiovascular system than just steps. It’s good to get 10,000+ steps a day but we also need to get our heart rate up and work our muscles and both of these watches will give you good guidance on that.

In the images below, Google Fit just gives me a breakdown of my day so far. It didn’t provide a snapshot of that particular workout which kinda stinks. This data is from Google Fit and provided through the Wear OS app on my iPhone.

Google Fit Move Minutes

GPS Accuracy

Now onto the GPS. Here the Vivoactive 3 Music redeemed itself. It connected to my position quickly (less than 10 seconds) and didn’t lose GPS signal throughout the 1-mile walk.

The Fossil Sport also connected very quickly but it had the advantage of using the built-in GPS in the watch plus the GPS on my iPhone XR. Actually, I wasn’t able to use the built-in GPS by itself. Google Fit didn’t give me that option which is strange. I’m going to have to do some more testing but using both sensors produces good results as I would expect.

The Fossil Sport estimated a distance of 1.04 miles while the Vivoactive 3 Music estimated 1.01 miles. So not much of a difference there. I did get a message that the Fossil Sport had lost connection at one point during the walk after I completed the activity but it doesn’t seem to have affected the distance estimate.

The steps were also very close with the Fossil Sport estimating 2320 steps and the Vivoactive estimating 2348 steps.

The Fossil Sport estimated I burned 133 calories while the Vivoactive estimated 89 active calories. Google Fit also includes basal calories in the estimate. With the watch estimating my average heart rate higher through the workout I would expect the calorie estimate to be higher as well, as it was.

Some of the data shown on the Fossil Sport after finishing the walk.

Unfortunately, I have the Fossil paired with an iPhone so I don’t get to experience the full functionality of the watch, as in viewing my activity in Google Fit complete with a map and having access to a number of other Wear OS apps. However, I will be testing the Fossil Sport with an Android smartphone too for the full review.

I’m really regretting to switching to an iPhone at this point because it limits the functionality of non-Apple products which really, really bothers me but that’s another story.

Luckily, I can use Strava with the Fossil Sport and see more details of my workout, including a map but I’d have to start the workout through Strava on the watch to get the data.

You’ll definitely get the best overall experience with a Wear OS smartwatch when paired with an Android smartphone but most of the features of the Fossil Sport work with iPhone.

But anyway, just focusing on the accuracy and performance of the heart rate sensor on the Fossil Sport, so far I’m very happy with it. I really didn’t know what to expect. I’m a bit perplexed by the heart rate results during this test on the Vivoactive 3 Music. I expected much better because it has performed well in most of the gym activities I’ve put it through, although I had previously noticed some quirky behavior.

Some of the data displayed on the Vivoactive 3 Music after the walk. Scrolling through the screen shows more data. View the Vivoactive 3 Music on Amazon.

We’ll see how it performs in the future.

I’ll be putting both of these watches through several more indoor and outdoor tests but in the first test between the Fossil Sport and the Garmin Vivoactive 3 Music, the Fossil Sport won and I wouldn’t have predicted that.

Indoor Test

I put the Vivoactive 3 Music and the Fossil Sport against the Polar H10 chest HR strap and, guess what, the Vivoactive 3 Music did very well! So I’m not going to write off its’ heart rate sensor.

It was very near to what the chest heart strap was indicating nearly the entire 45-minute workout which consisted of walking and running on a treadmill.

Now for the Fossil Sport, I’d noticed in a previous test on the treadmill that once I began running and my heart rate got about 140-ish it would get stuck at a certain number and took a long time to come back down.

It did the same thing early on in this test as well, at least the first time a ran and got my heart rate up but it did fairly well throughout the rest of the workout. You can see the comparison below.

I used Strava on the Fossil Sport to get a heart rate data. Unfortunately, Google Fit through Wear OS on the iPhone doesn’t give me workout data which really, really stinks.

Anyway, the Fossil Sport seems to do very well for less intense workouts. If you’re a runner, you’ll probably want to look to something else other than the Fossil Sport but if you primarily walk and/or do casual biking, it should be fine.

But overall, the average heart rate results between the Fossil Sport and the Polar H10 heart rate sensor were fairly close. The Fossil Sport estimated my average rate at 130 bpm and my max HR at 149, while the Polar H10 estimated my average rate at 124 bpm and max at 150 bpm. The Garmin Vivoactive 3 Music estimated average HR at 124 bpm and the max at 157 bpm.

Garmin Vivoactive 3 Music Heart Rate Results

Fossil Sport Heart Rate Results
Polar H10 Heart Rate Results

So not a huge difference there but as I watched throughout the workout, the Vivoactive was consistently closer to what the Polar H10 was showing.

While optical heart rate sensors on fitness tracker have improved greatly over the past couple years, if you want the most accurate results you’ll want to get a chest heart rate strap, like the Polar H10.

You can actually use the Polar H10 on the Garmin Vivoactive and it will use the data from the heart rate strap. You can’t do this with the Fossil Sport. Also, you can use the Polar H10 with your smartphone and through the Polar Beat mobile app monitor your heart rate which is what I did in this test. You can check the price and availability of the H10 on Amazon.

So, I’m hoping that first outdoor test with the Vivoactive was truly a fluke. I’ll test again but right now there’s nearly a foot of snow on the ground and we’re supposed to get hammered again with another snow storm this weekend, so it may be a while before I can do the same test. Welcome to Illinois in January!

I love the red and white style of the Fossil Sport. It’s also available in other colors.

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Last Update: January 14, 2019