Heart Rate during swimming Fexin 7s

New Fenix 7s owner here and excited to be able to track my heart rate while swimming but it's not accurate. The watch indicates I was above 180 BPM for more than 30 minutes! When I turn it off and go back to the standard heart rate monitor on the watch, it shows around 118, which should be close. Any ideas on how to get the swimming heart rate accurate? It screws up all my other metrics when it records it at such a high level.

0 S.M.R. over 2 years ago

Is the strap tight when swimming?

0 Dr Phil over 2 years ago

2543417 said:
Any ideas on how to get the swimming heart rate accurate?

There's no guarantee that even with the strap properly tight and the watch correctly positioned that you will get accurate HR when swimming. There's too much going on with flexed wrists and water possibly getting between the watch and the skin for that to happen. That said, there has been a definite improvement with the F7 series watches over those that came before. With the F6/Marq I would always get what looked to be a reasonable graph but it was always 30 to 40 bpm too high. A strap (HRM-Pro) for example really is needed for swimming to be sure of getting accurate information. However, when I compare the heart rate from the wrist to that from a strap I do see little difference between the two when using my F7 or Epix.

0 2543417 over 2 years ago in reply to S.M.R.

hmm - I'll try loosening it the next time. I was putting it on pretty tight.

0 2543417 over 2 years ago in reply to Dr Phil

OK - I can keep playing with it to see if the accuracy improves. It's just when it goes so out of whack, it screws up all the analytics. I suppose I could turn off the HR but I really wanted this watch exactly for that reason. And, you know I can't wear at a strap - it would ruin my look in my swimsuit

0 entify over 2 years ago

Chest strap ( HRM Pro, HRM swim) is the only way.. Optic heart rate sensors is bad in water

0 Dr Phil over 2 years ago in reply to 2543417

2543417 said:
And, you know I can't wear at a strap - it would ruin my look in my swimsuit

Know what you mean. I'm ok when the strap is beneath my wetsuit I do get some funny looks in summer when I go without the wetsuit. In the pool I have worn a triton to keep the strap from moving in turns too.