Reviewed: Fitbit Sense Smartwatch

Jam-packed with sensors, Fitbit’s latest has a lot of data, but is any of it useful to triathletes? We break it down.

Review Rating


With literally more sensors than even Fitbit knows what to do with, this watch is far more wellness focused than tri-training specific.


Great form factor
Beautiful screen
Piles of recovery/sleep/wellness feedback
Surprisingly good battery
SpO2 measurement
ECG functions to come


Very glitchy touchscreen/apps
Very basic training data
Few “actionable” items given the amount of sensors
No open-water swimming or multisport modes






Fitbit, available at

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The big selling point around Fitbit’s newest smartwatch is actually in its name: This watch has more sensors built in than almost any other lifestyle smartwatch on the market. The most notable being SpO2 (pulse oxygen), EDA scan, skin temperature, and ECG—though the ECG function isn’t supported just yet. These are all fantastic metrics, but as we’ll talk about later, these are more focused on general wellness that targets people who consider themselves either barely active or only slightly active. Some of this applies to a training triathlete, but not as much as it would for someone who’s just trying to lose some weight or get healthy. Almost as an aside, the Sense also has some swim/bike/run training modes, and we’ll look at those below. As you’ll see from our FitBit Sense review, the important thing to know is that the Sense is first and foremost about striking an “active balance”—something that triathletes may inherently never do.

Related: Smartwatch Reviews From a Triathlete’s Perspective

Fitbit Sense Review: The Wellness Basics

I certainly don’t want to dissuade anyone from buying the Sense based on the fact that wellness sensors and data aren’t important to triathletes, but it’s essential to understand that that’s the purpose of this watch. The Sense will provide you with an endless stream of data like a stress management score, an EDA scan, (eventually) a very cool ECG app to detect potential irregular heart activity, SpO2 monitoring, heart-rate variability and always-on tracking, as well as breath rate, and others. This is a staggering amount of information, and in an era where health is not only important but sometimes tenuous, these are important metrics for a lot of people. This watch will tell you quickly if something is “off” with your health, and in theory help direct you to the root of the issue, but we’ll get to that more below.

Fitbit Sense Review: The Training Basics

As far as triathlon training goes, the sport functions and data analysis on the Sense are extremely basic. This smartwatch has pool swimming (no open water), indoor/outdoor cycling and running with GPS, but not much else. There are no options for route mapping, external sensor connectivity, or multisport. In fact, the heart-rate accuracy on the Sense is surprisingly not amazing and the GPS tracking is just ok. You can control and store onboard music with this watch, along with lifestyle features like weather and notifications, but there isn’t much else of note when it comes to training.

Fitbit Sense Review: Other Stuff

Knowing that the Sense has never been designed as a serious multisport training device is important, but there are a few other notes on this watch—even if you’re all-in on the wellness features. First, the battery life is actually surprisingly good, given that the touchscreen is quite bright and active. Unfortunately, the software powering the touchscreen seems to be a bit slow, as it’s tough to use and prone to both misqueues and freezing. On that same note, the only “button” on the Sense is awkwardly located on the under part of the left side of the screen—a tough reach and definitely not intuitive. Finally, even with all of the sensors lining this watch, Fitbit seems to be struggling with a good way to present the information in a format that people can actually use. It’s one thing to know your skin temperature is too high or too low, but it’s another to understand what to do with that knowledge. Same goes for the Sp02 feature that requires quite a lot of wearing to even produce a number and is tough to take action upon. 

Fitbit Sense Review: Conclusions

With the long list of wellness sensors, even in that category, the Sense seems to fall a bit short. This watch feels a little bit like an early release (for instance the much-vaunted ECG app still isn’t out yet as of this writing—a big selling feature), and I think users will have a lot of legwork ahead of them to make sense and use of all of the data this smartwatch provides. That’s not to say updates won’t cure some of the confusion, but this felt a little more beta than a finished product. In the realm of serious multisport training, there is little need to purchase this watch, but it could still be a great gift for anyone who wants a treasure trove of personal data to keep themselves healthy or get more active.

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