HRM accuracy

For me HRM data seems to be correct. I have no comparison in the water, but made a test during cycling, and it was spot on. During the swim I do not see any wild deviation from the awaited value. Maybe I am just lucky :)

Note, that the strap must be snug (but comfortable), and should be worn a bit more away from the hand (not on the wrist bone!)

(btw, during table tennis 88 BPM is way unrealistic, unless you play with your 5 yrs old kid. I would guess between 110 and 140 during recreational play)

It also recorded AVG HR of over 130BPM when I selected 'Cardio' and went for a walk! I hope thats not correct, since my 4-mile Open Water swim sessions per week, plus my daily recreational table tennis isn't working ;)

I'm going to compare the next session by actually measuring my HR manually. Maybe my iWatch has been kidding me all these years ;)

So i finished my table tennis, and measured 96BPM (proper medical method), and watch indicates 137!

Also, as soon as I stopped the activity and saved it, upon returing to the home screen, the heart rate shows 126 briefly, and then jumps immediately back to 83?

You mean on the watch face?

Note that HR on the watch face is refreshed about every minute (I guess the same time as the minute reading is refreshed). So the 126 could be a nearly one minute old value, and while you were measuring the HR, it went back to 83.

If you want real time reading, go into the HR widget, that has a refresh rate of about 1 sec.

PG, No. What I mean that as soon as I activate 'Cardio' workout, I see the Timer field at the top, and the current HR at the bottom, which is refreshed quite often. What I see is that by simply looking at the watch and holding everything still, the HR field rises steadily from the resting value to over 120, in about 10-20 seconds! Wow!

The Swim2 seems very accurate at low heart rates [40-60] (ie matches Polar h10) but when i'm exercising i'll see heart rate readings ~ 40bpm > Polar h10,  I'd be really surprised if at age 69 i have a max hr ~ 190.  During a treadmill stress test at a cardiologist's last fall i topped out ~ 178.  I'm wondering if getting the garmin swim chest belt makes a difference as - duh - swimming IS why i got the Swim2.

I did a comparison on sw B2.2 and a polar oh1 on the upper arm while swimming in pool

and they followed each other within 2 bpm in range between 130 to 160 so I’m satisfied.

There seems to be a lot of us with exaggerated HRM reported. My Swim 2 does a good job when I'm not working out 42 to 55 BPM. Somewhere around 70 to 80 BPM it starts reporting 140 to 180. My Polar Wearlink and RCX5 reports around 80 BPM. I have tried on outside of my wrist, on the inside of my wrist and both left and right arms with the same results. My max HR is around 120 BPM with a condition called "chronotropic incompetence" (79 YO).

As an aside, the Swim 2 linked to my MyZone MZ3 belt at an RPM class and used that belt during the workout and was accurate. So I tried the MyZone in the water and it didn't work. The connection was probably Bluetooth not ANT.

Maybe there could be an improvement (update) if we could adjust the sample rate. My understanding is that it is increased when you start an activity maybe that is throwing it off somehow.