Over a year later... how is the optical HR sensor in the 235?

hi,

I bought the forerunner 235 short after release in my country (it was the end of november 2015 / beginning of december 2016?) and returned it after 2 weeks because the optical heartrate was a disaster.
In september 2016 I did try it again and I love it now! Optical heart rate is good (comparable to the optical readings of my previous tomtom runner) so in my opinion it has improved a lot!

Have run over 2,600 miles since mid November, 2015 with the 235. I guess I am lucky,no real issues with the Elevate wrist HR. Garmin has updated software several times since the Watch hit the streets and those improvements seemed to have been beneficial to most folks. Have I had issues with wonky HR readings sometimes? Yes. But I have experienced those things with various HR straps over the years.
I don't monitor HR other than while running so my experience may be limited compared to others. Nick

Only ever wear mine when running. Had it about 9 months and overall I'm happy. A couple of minor quibbles, can take a while for the HRM to get a lock, stop flashing, but there's a work around, go in and turn off then turn it on again and get a lock typically in 5-30 seconds.

You used to get a notification that it's locked, same as when you've got GPS, but for some reason this was removed during a SW update!

Had mine since December 2015 and while it works OK on average I don't think you'd be happier with it now than you were originally. It still has cadence lock, it still loses the plot with ridiculous values (a reboot before running sometimes helps).

The updates they made in the first part of 2016 did help but at the same time it got warmer and that helps HR optical sensors vs the cold that restricts blood flow to the wrists. Problems started again with v6.30 around October if memory serves and it wasn't that cold yet so...

Are the various generations of the "Elevate" sensor documented anywhere or are they just passing mentions by Garmin each time they release a new generation ?

Had mine since December 2015 and while it works OK on average I don't think you'd be happier with it now than you were originally. It still has cadence lock, it still loses the plot with ridiculous values (a reboot before running sometimes helps).

The updates they made in the first part of 2016 did help but at the same time it got warmer and that helps HR optical sensors vs the cold that restricts blood flow to the wrists. Problems started again with v6.30 around October if memory serves and it wasn't that cold yet so...

Are the various generations of the "Elevate" sensor documented anywhere or are they just passing mentions by Garmin each time they release a new generation ?

Ray Maker of dcrainmaker.com says there are 3 generations of Elevate sensor although its more like a running change, I don't know Garmin has even referenced a change ever...

1. First generation is what you saw in the 235, Vivosmart HR, Fenix 3HR and Vivoactive HR.

2. Second generation is what you see in the 35, 735 and Chronos line, it basically uses a slightly different shape led bulbs, more round than rectangle. It's unclear why the change was made or if it effects performance. It maybe just a different supplier or cost savings etc.

3. Third generation is what you see in the upcoming Fenix 5 and the big news here is it uses massively less battery power so Garmin will now be able to allow 24/7 storage of HR measured every 1-2 seconds instead of the crummy every 10 minutes to several hours (during non-workout times) seen on all the above listed Garmins. Hopefully the accuracy remains the same or gets better. The only other mass market company that has done 1-2 second all day recording of HR is Fitbit and their accuracy is horrible during workouts, nothing close to Garmin's Elevate although it does do ok for resting HRs.

Temperatures up today (at last) from 0 celsius to 8 celsius and...the HR was pretty much perfect (had a cheststrap for comparison) for my 50' easy run (72% Max HR).

Did you wear two watches then? I don't believe there is a way to see HR strap data and optical data on one watch.

CW

Yes I had my old FR610 on the right wrist showing Lap Pace and HR. The cheststrap was the HRM3 with the first version of the fabric strap.

The Wrist Monitor is NOT live 24/7

Most of the time it's simply "filling in the blanks" between polling intervals. Note, the polling intervals are somewhat variable due to the Activity setting but every single activity does Polling. IMO for Interval Training the wrist monitor is 100% USELESS. To be useful for Interval Training you really need a continuous live trace and that means the only choice is to use a Chest Monitor which is a 100% live tracking device. If you want to see why I state this see the following link to a post I put up today. Based in this mornings experience the Polling interval for Indoor Run is somewhere in the range of 1.5 to 3 minutes, not nearly frequent enough for interval training. Saw lots of "overshoot" on the heart rate during rest intervals when the heart rate was rising while I was at a complete stop. I've also seen many cases where during a run at a steady pace for extended periods of time will have points during the run where the heart rate trace will go totally off track, either way low or way high. IMO the Optical Heart Rate monitor is only useful when you are sitting at a desk or asleep, for anything more active than that you can expect a lot of periods that are 100% fiction during a days heart rate trace.

https://forums.garmin.com/showthread.php?369666-Junk-results-from-the-wrist-monitor