Inaccurate HR readings while doing HIIT?

Former Member over 7 years ago

Good Morning everyone.

I've been experiencing problems with the wrist HR on my 5x on anything that requires wrist movement.

I've tried moving it up on my arm, tightening it, loosening it, restarting it, locking keys.
But every time i am doing HIIT, particularly INSANITY, which requires a lot of up/downs and pressure on the wrists, the HR stops properly reporting.
And it doesn't move even during the 30 seconds rest we get in between sets.

I've used my wife's Scosche Rhythm+ armband and as I was peaking, feeling my heart beat out of my chest, my phone was showing me at 152BPM while the watch was showing me at 90BPM.

I don't know if it's sweat, or if it's the movement, or if I am doing anything wrong, but I am pretty irritated with the prospect of having to buy a standalone HRM.

Has anyone experienced the same problem?
Any tips to get this fixed?

Thanks in Advance.

0 ikim1967 over 7 years ago

Fairly common situation - people report that on a lot of activities that require wrist movement - such as elliptical trainers, etc. I see it while riding the mountain bike too - seems worse on the 8.0 platform - but I'll ride, can feel my heart out of my chest and the watch says 90 or something. After a couple of miles it kicks in and seems around where it should be. Sometimes, though, it will also pick up from the start.

I have a polar BT strap that I bought because my previous device(s) also wasn't that great at wrist HR (I don't believe any of them are - my neighbors posh Apple 3 is pretty bad) - I have got in the habit of wearing that more on rides. It picks up on more subtle changes anyway - even if the watch is matching the perceived HR.

0 Biff over 7 years ago

Yep, common. Get a chest strap.

0 Former Member over 7 years ago

Optical HRM are only for novelty purposes. Get a good chest strap.

0 mcalista over 7 years ago

OHR (regardless of brand) tends to be slow to respond to changes in heart rate. As heart rate (even measured instantaneously) is a lagging indicator of effort anyway, OHR with HIIT is just all over the place.

I find I get good results for running (even at high intensity), but as soon as intervals are involved, I use a chest strap instead.