Support the use of an external heart rate monitor

[Matt_Harrell]

I'm a fairly serious cyclist. I'd love to see my Pixel Watch 4 support the use of an external HR monitor (I use a Garmin chest strap monitor). As good as the HR monitor is on the PW4, it's still not going to be as good as one that directly measures the electrical signals that trigger a heart beat.

[haddat]

Totally agree. I used the Garmin HR chest belt too with my Garmin watch. I'm missing this feature with my Google Pixel Watch 4.

[BRogers80]

Yes, please. I always use a ecg chest strap when doing trainig sessions with high heart rate.

[slowerthanyou]

Google is definitely losing sales due the lack of external HRM support. Fitbit won't even acknowledge that a chest strap is far superior to an optical wrist-based heart rate monitor for many types of exercises. It's just stubborn.

[tmizster]

I couldn’t agree more. I have no idea why Google doesn’t just add support here. They’d pull in a ton of Garmin and serious fitness users if they did.

The new AI app is awesome, but not when it’s fed garbage HR data. I’ve been testing the PW4 and sometimes it’s great, but in many cases the HR is so far off I can’t use it. The other morning I did a short, easy warm-up run before a hill workout and my PW4 was showing a HR of 174, while my Garmin + HRM was correctly reading 128.

Then I have to read the Fitbit AI telling me all these things about my incorrect HR. "Great effort, you got out strong with a 174 heart rate!" Garbage in, garbage out.

That said, I do like the direction Google is going. If they added this one feature, they would have something powerful.

[slowerthanyou]

That's what I was afraid of. I ended up buying a Garmin 965 directly
because of the lack of HRM strap support. My wife is going to try the PW4
for running and indoor cycling, but I do not have high hopes given your
input.

[Matt_Harrell]

The accuracy of the PW4's HR monitor is likely going to depend on what activity you're doing.  I believe that DC Rainmaker and some other reputable reviewers have all said it's quite good for an optical wrist-based system.  I will say that I've had problems with two consecutive chest strap HR monitors in the last couple of weeks, and while I wait for a new one to arrive from a different brand, I've been broadcasting the HR from my PW4 on my trainer rides, and it's been doing great.  It's always been at least reasonably close to what the strap was showing (via the training app), sometimes with a slight delay.  Still, I REALLY want it to support external HR monitors.  When they're actually working, they'll always be the most accurate.

[tmizster]

My experience with the PW3 and PW4 is that they often fall into bad cadence lock on runs. It eventually corrects, but not before all of the HR metrics are whacked out (and sometimes it will jump back to crazy-high HR again later in the run). Like I mentioned in an earlier post, when you know the data is totally wrong, it has a ripple effect on everything else the Fitbit side is analyzing, e.g. VO2 max, recovery time, fitness level, etc..
I don't want a chill zone 2 run to be looked at as a high heart rate effort!

Apple Watch seems to do a better job here with optical HR, but both Apple and Garmin pair to external chest HRM straps, which is the way to go if you care about accurate heart-rate data.

Please, Google... add support for this.

[haddat]

Totally agree.
But I doubt that Google will do us the favor.

Unfortunately, that is not the only shortcoming of PW4 & Fitbit.

[el_al]

Running in cold, skiing, puting the wathch outside the clothes for better visibility, avoid overtightening the wrist ... there are many common situations when wrist HRM is not enough.

It seems that they are overprotective with health data, and the type of bluetooth connection that transfers HR is not as secure as it should be. Nevertheless, that is an issue of the HR band manufacturer, not Fitbit itself.

Also, as many people is eager to pay 60€ for the official watchband, it is not unreasonable to think that we would pay 100€ for an armband  or chest HRM monitor from them, with a safe pairing, although I think it is not the way to go (stick to industry standards).

[tmizster]

Garmin added optional encryption to the HRM 600 chest strap reccently to comply with upcoming European Union regulations regarding the transmission of personal health data. It should't be that hard for Google / Fitbit.

I agree with you, most people who want this would likely be fine spending more money on a Fitbit branded chest strap.

[slowerthanyou]

The security issue with external HRM using Bluetooth is a misleading excuse at best. The use of external Bluetooth HRM devices is a world standard supported by all major fitness device manufacturers. Fitbit stands alone as the only company that does not include that functionality. Blaming the "band manufacturer" is deflection.

The GPW4 can broadcast it's HR data over Bluetooth, using the exact same insecure connection. They are not concerned when it's their heart rate data that is insecure, and thus contradict their own argument.

Google/Fitbit have made a decision to block external HRM because they want the raw sensor data from the watch. They can't get that if they allow external sources, so they made the absurd excuse that their sensor is as good as a chest strap. This is exactly why they haven't released their own chest strap or arm strap HRM; the raw sensor data is far too much for a Bluetooth connection to handle.

The security argument is simply a convenient excuse for Fitbit to own the whole data path. It's a business decision, not a security issue.

[tmizster]

Agree. I think someone just posted it as a theory. There is no evidence from Google that a security issue is holding up support for this. Note, Apple Watch, Garmin and others have been supporting external HRM for years. And pretty much all gym equipment can connect.

[koles]

Adding support for external heart rate monitor is a software feature which can be added with SW update. Google please add this feature!

[whitehatjoker]

Yeah, absolutely agree. I've been doing CrossFit and pixel watch 4 doesn't track it even 40% accurately in comparison with Polar H10. I've replaced pixel watch with Amazfit BIP 6 which costs around 100 bucks. I don't understand this company at all.

[Ravin21]

Dear Fitbit and Pixel Watch Team,

I am writing to request a feature that is extremely important to me and, I believe, to many other users: support for external heart rate monitors (such as Polar H10 or Polar Sense chest straps) on Pixel Watch and Fitbit devices.

Accurate heart rate monitoring is essential for me, both during daily activities and especially while exercising. Unfortunately, wrist-based heart rate sensors are often inconsistent and unreliable during workouts due to movement, sweat, and changes in wrist position. This is a well-known limitation of optical wrist sensors across the industry.

Chest-strap heart rate monitors are widely recognized as the most accurate option, particularly for exercise and medical-related monitoring. Allowing the Pixel Watch to automatically use an external heart rate source when available would greatly improve accuracy without negatively impacting users who prefer the built-in sensor.

For me, this is not just a convenience — it is a necessity. I need to monitor my heart rate continuously, including during exercise, and I rely on accurate data. Adding external HR connectivity would be a truly inclusive feature that supports users with medical, training, or accessibility needs.

I am currently considering switching to a other watch solely because other supports external heart rate monitors. However, Garmin lacks cellular connectivity, which is a feature I rely on. I should not have to choose between cellular connectivity and accurate heart rate monitoring, nor should I have to wear two watches at the same time.

Supporting Bluetooth external heart rate monitors would:Yes, when I'm done

• Improve exercise accuracy

• Support users with medical or accessibility needs

• Align Pixel Watch with industry standards

• Not disrupt existing users who prefer wrist-based monitoring

I sincerely hope you will consider adding this capability in a future update. It would significantly improve the Pixel Watch experience and help retain users like me who truly want to stay in the Fitbit / Pixel ecosystem.

Thank you for your time and consideration.

Kind regards,
Ravin21