wrist-based heart rate for swimming

No. It won't be coming to the 5 series.

The FR945 and Fenix 6 series have a different optical sensor on them. Only ones with that sensor are getting wrist-based swimming HR. The reason they don't roll it out to earlier ones is because it's just not reliable enough in water, but the new OHR sensor does seem to beat the threshold they set.

All day battery on the other hand, as far as I can tell isn't based on any new improved sensors, so it's just a software reason as to why that's not coming to the 5 series. Of course, I'm open to the possibility of me being wrong about this.

This works for Fenix 5 as well. THANKS.

Works SPOT ON my Fenix 5x plus. WOW. 

Hi MarcWilensky

I'm trying with a Fenix 5X. I have an HR enabled data field in the pool swim mode. I have activated the boradcast HR mode, but when you say "switch off HR mode", do you mean turning off the HR in the Status from "Auto" to "Off"? ...

The HR data screen appears with the bars as if it is not reading nothing.

I have an HRM-TRI and I have even deleted it, but I'm not able to get HR measurements. Thanks!

How did you do it?

Once you have the swim widget activated, activate broadcast HR. HR will show in broadcast mode. Now switch off HR in the broadcast mode. When you go back to the swimming mode, you'll see that the HR is still active. During the swim you will be able to see HR if you have that particular screen showing. After your swim when you sync with Garmin Connect, you'll see your aerobic and anaerobic activity. (The two circles that have a number attached to them). You will not see your heart rate in a graph like you'd see swolf etc. Garmin could probably activate the HR graph, but that would impact sales of new devices featuring HR while swimming...and so it goes on.                                                                                                          How accurate is the HR using the optical sensor?..Not sure, but then how accurate is any sensor using Optical HR measured from the wrist. It's a guideline more than anything else measuring the effort you've put in. In any event, it's far easier and more comfortable to just wear the watch than the blue swim strap.