Fitbit Sense: We acquired the insider scoop from Fitbit on temperature monitoring, ECG and extra – CNET

Fitbit Sense: We acquired the insider scoop from Fitbit on temperature monitoring, ECG and extra – CNET

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The Fitbit Sense is the corporate’s first main watch replace because the Fitbit Versa in 2018, and it provides quite a lot of new sensors: an ECG much like the Apple Watch and Samsung Galaxy Watch three, stress sensing by way of an electro dermal exercise pores and skin response sensor, and temperature sensing much like the Oura ring.   

I have not examined the Fitbit Sense but as a result of the Fitbit Sense I used to be despatched is not set as much as pair with Fitbit’s app but, however I am holding the $329 (£300, AU$500) watch in my palms. Whereas I am unable to say how all these sensors will work in on a regular basis use, I can say the watch’s construct has some enhancements over the earlier Fitbit Versas. The curved watch form is the same thickness to the $199 Versa 2, however has extra metallic and glass within the end.  

The facet button for beginning exercises and calling up Amazon Alexa (or now, Google Assistant) has been changed with an indented contact space that vibrates when pressed, just like the Fitbit Cost three and four have (will this be higher when one is sweaty? I do not know). There is a speaker now, for voice assistant and cellphone calls. The Sense wrist straps detach much more simply than the Versa’s ever did (which additionally means: new customized watch straps). The charger can also be new, a magnetic snap-on that is extra much like what the Apple Watch has and is meant to completely cost in about 15 minutes. It is higher than the alligator-clip-charger Fitbit Versa had earlier than.

There are different overdue additions too, like GPS, a redesigned optical heart-rate sensor that guarantees higher accuracy when operating and sleeping, and perhaps richer knowledge assortment for future well being analysis (optical coronary heart fee is already the place blood oxygen, coronary heart fee, respiration are drawn from; Samsung’s already exploring blood strain prospects, too). Fitbit’s latest software program updates add particular SpO2 blood oxygen readings to Fitbit watches, and a day by day “stress readiness” rating that can add measurements like respiratory fee to the combo, that are additionally a part of a brand new step-down mannequin being launched Tuesday, too, the $230 Fitbit Versa three. 

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However the Sense’s formidable triple-add of latest sensors factors in the direction of Fitbit’s striving for brand spanking new knowledge to research and add to a rising machine-learning well being image, which makes this appear like Fitbit’s closest try and a health-and-wellness super-wearable. I might welcome the thought of one thing on my wrist that may assist me perceive how I am doing every day, even past how a lot I am strolling round and exercising.

I’ve seen concepts round a well being super-wearable come and go over years. Will Fitbit Sense be that system? Since I have not reviewed it but, the reply for now’s a powerful perhaps. And Fitbit seems to be to be leaning on its premium subscription well being service, launched final yr, greater than ever to take advantage of Sense’s knowledge (extra particulars on that under).

There are a couple of causes to attend and see. New sensors on wearables are at all times a little bit of an unknown. Possibly Fitbit is breaking by means of to a complete new territory right here. Or, perhaps not. I bear in mind different wearables’ promising new sensor tech earlier than (the Jawbone Up three had bio-impedance; the Microsoft Band 2 had UV sensing, after which there was the sensor-studded research-focused Samsung SimBand), and a few of these by no means did something to reside as much as their ideas. Will EDA make as a lot of a distinction on a watch as Fitbit guarantees? I am extraordinarily curious to search out out. Temperature sensing continues to be fairly distinctive. ECG is changing into a typical customary on health watches.

However how will these all interconnect? For that, I talked with Fitbit’s Shelten Yuen, head of analysis, and lead analysis scientist Conor Heneghan about what these sensors are aiming to do.


The Fitbit Sense’s temperature sensing will occur nightly and present relative adjustments over time as an alternative of a particular studying.

Richard Peterson/CNET

Temperature: Not like a thermometer, however a nightly relative baseline 

Temperature on wearables began getting quite a lot of consideration after the coronavirus pandemic shut down the world this yr. The potential for detecting signs of sickness by means of a watch or ring with temperature scanning, or pulse oxygen readings, started to really feel like a promise of wellness forecasting. 

“The origin of this was prepandemic,” Fitbit’s Yuen tolds me over a Zoom name. “Some time in the past, we had this speculation that with a wearable system, the temperature sensor might be used to detect a fever and even predict a fever was going to happen.”

The $300 Oura ring has turn into essentially the most acknowledged temperature wearable, however there aren’t many others. The Fitbit Sense appears to work in the same manner, accumulating pores and skin temperature whereas sleeping and delivering outcomes the subsequent morning to point out relative change.

It does not do an prompt temperature scan, and it will not give particular customary physique temperatures to point out when you’re 98.6 or 100.three, as an illustration. However it’s going to present relative temperature adjustments every day. That is as a result of pores and skin temperature readings on a wrist are completely different. I have not examined the Sense but, however I wore an Oura ring for months to verify my temperature, and it was largely a graph of gently fluctuating relative scores. (I wasn’t sick throughout that point, so it is onerous to evaluate.) The temperature consciousness is extra like another knowledge level in a set of factors that Fitbit’s utilizing for its day by day stress rating calculations.

What’s actually wild is Fitbit acknowledging that current Versa watches have already got a temperature sensor that’s used for system battery administration. These sensors helped the  firm put together for what the Sense may do. “We’ve some knowledge from that to direct the place this might go sooner or later,” Heneghan says.

These different temperature sensors usually are not as skin-focused because the Sense’s temperature sensor, and might not be as correct. Nevertheless it may assist flip a bunch of Fitbit Versa units into temperature-aware wearables, including quite a lot of units into the combo quick for potential Fitbit analysis. It sounds just like the Sense’s temperature sensor is extra fine-tuned for the job.


The Sense’s rear sensors and metallic rim on the face measure temperature, ECG, and galvanic pores and skin response for stress measurements.


Stress sensing occurs in a complete new app

The Sense’s electrodermal exercise, or EDA, sensor makes use of the metallic outer rim of the Sense to conduct and get a studying when the palm of your hand is pressed in opposition to it. Fitbit has a brand new EDA app that can take a studying over time and sense your total stress. However this will likely be a unique app than the center rate-based Chill out app that presently calculates coronary heart fee variability and in addition encourages mindfulness. Fitbit’s additionally launching a brand new set of mindfulness and meditation options into its Premium subscription service that particularly makes use of the EDA sensor.

“Your physique’s sympathetic nervous system is sending little alerts to your sweat glands on a regular basis,” Heneghan says of the EDA sensor. “That creates a tiny bit of additional moisture to your pores and skin, and that adjustments the conductivity of your pores and skin.”

The 2-minute stress scan within the app would require you to carry your hand over the watch the entire time, as would any meditation options utilizing EDA.

“You place your hand over the system, and principally it’s a very, very small microcurrent that is going by means of the palm of your hand. And we are able to choose up the person spikes of nerve sympathetic nervous system exercise” provides Heneghan. “Within the EDA scan app, we will rely up the variety of spikes we see each 30 seconds and report that again to you.”

ECG, however no background arrhythmia scanning but 

The Sense’s one-lead electrocardiogram sensor, which Fitbit and Apple name ECG, however is similar as what docs name EKG, works by finger-pinching the metallic bezel on the perimeters of the watch face to finish a circuit. It takes a studying that scans for potential atrial fibrillation very similar to the Apple Watch, latest Samsung watches or different units such because the Withings Transfer. Like different watch ECG options, the Sense will not detect coronary heart assaults or different circumstances that extra superior ECG readings may choose up. Additionally, the ECG function continues to be ready for FDA clearance, a course of that is anticipated to be completed this yr.

And the Fitbit Sense will not repeatedly scan coronary heart fee for indicators of arrhythmia — not less than not but. The Apple Watch already does this, and Fitbit says it is engaged on it. The corporate introduced its larger-scale atrial fibrillation research in Might. 


The redesigned optical coronary heart fee sensors on the again measure gentle by means of completely different areas directly.

Scott Stein/CNET

Extra correct heart-rate readings may open different measurements

It is at all times onerous to forged ahead and anticipate an excessive amount of of sensor platforms, as a result of it is unclear the place outcomes will land. As an example: Fitbit’s lengthy touted sleep apnea detection nonetheless hasn’t arrived, regardless of guarantees for years. “We’re form of participating with the regulatory course of, and the actual problem is simply getting sufficient quantity of knowledge to show out what we have already got,” Fitbit’s Heneghan says to me about progress on detecting sleep apnea.

In the meantime, analysis initiatives with the Fitbit Sense’s new sensors may discover wellness forecasting by means of temperature and SpO2, however no particular plans are in place but with any research. “Sooner or later, we hope to develop a regulated SpO2 function that might assist with sickness detection and could also be an indicator of potential persistent respiratory circumstances, like COPD (persistent obstructive pulmonary illness), or acute sickness like COVID-19,” Fitbit CEO James Park tells me in e-mail reply to my questions.

Fitbit’s present COVID-19 symptom detection analysis has been targeted on heart-rate variability, resting coronary heart fee and respiration fee as metrics, which CTO Eric Friedman says “can detect 50% of COVID-19 instances a day earlier than onset of signs with 70% specificity.” Fitbit will likely be including sleep knowledge, temperature and SpO2 blood oxygen measurements into additional research.

The center-rate studying enhancements for the time being appear to be about serving to accuracy whereas operating and sleeping, to forestall gaps in knowledge. Nevertheless it may nonetheless open up different channels too: Samsung and Valencell are attempting to crack blood-pressure readings by means of PPG. Fitbit is not that but, however Park says, “On the subject of coronary heart circumstances, we proceed to discover further metrics like pulse arrival time – a metric which may sign that your blood vessels are getting stiffer, which might be a sign of coronary heart illness or hypertension.” 

However on the subject of different readings pulled from coronary heart fee, Yuen provides: “We’re hoping to discover this knowledge set after which perhaps unlock its potential sooner or later. I do not wish to overpromise. However are we curious about issues like this? Completely.”

Fitbit is basically leaning on you paying for Premium

Loads of the day by day metrics and instruments Fitbit mentioned with me depend on Fitbit’s $9.99-a-month Premium subscription service, which launched final yr and now has over 500,00zero subscribers. Some measurements like a particular SpO2 measurement will likely be out there by means of a free watch face and in additional restricted units of readings on the free app, however longer historical past and evaluation comes with the premium service. 

That Premium service is an additional price, and in addition an additional lock-in. Fitbit’s knowledge does not circulation into Google Match or Apple Well being like another wearables do, and it means staying in a channel that may really feel limiting, particularly since most individuals have an rising circulation of well being knowledge from different sources.

Fitbit features a six-month free trial of Premium with the Sense (and a yr with its lower-cost Encourage 2), however ultimately that is going to be an additional charge. Google and Apple haven’t any related subscription well being/health service but, however there are many teaching and health apps that do.

Premium does not appear needed, however for lots of what the Sense gives, it might be the way in which you’d wish to get essentially the most out of the system.


The Fitbit Sense seems to be formidable. How will it dovetail with future Google wearable plans?

Richard Peterson/CNET

What does this all imply with Google?

Fitbit’s pending acquisition by Google has been underway since November, and Fitbit’s subscriber base and knowledge archive may turn into a launchpad for a brand new era of Google well being wearables. However the Fitbit Sense has no added hook-ins to Google’s ecosystem, aside from added Google Assistant voice assist along with assist for Amazon’s Alexa voice assistant. Park would not touch upon Google. “As you recognize, the merger is topic to customary closing circumstances, together with regulatory approvals,” he says. “Till the transaction closes, we proceed to function independently and are targeted on persevering with to create thrilling, revolutionary units and companies for our customers.”

The Fitbit Sense may be the final new Fitbit underneath the Fitbit model. Or, perhaps it is the blueprint for a brand new era of future units. Clearly, these new sensors are the place Fitbit needs to go subsequent. However what we do not know is how a lot Fitbit’s future will appear like its current as soon as Google enters the image.

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