Why trail loop compromises heart rate reading in swimming?
Apple Watch ultra, most updated software as of 05/25/2023.
Like many other owners, I have been rather disappointed that the Apple Watch Ultra fails to measure my heart rate when swimming, especially freestyle.
Previously I owned Series 2 and 4, both were far more capable than this brand new Apple Watch Ultra.
This makes the watch band type suspicious — so I bought a sport band (fluorinated rubber) just the same as I got with my old watches and swapped out the trail loop band that came with the Apple Watch ultra.
Immediately I see an improved heart rate reading in swimming last night.
So the question is, what exactly is happening here? Why does the trail loop band makes the Watch so difficult to read heart rate???
Apple Watch Ultra, watchOS 9