Since owning an Apple Watch, both Series 2 and 4, I’ve struggled with the heart rate sensor whilst running. This lead me to buying a dedicated chest strap heart rate sensor. I’ve had both a Wahoo and a Garmin and they both seem to work well until they don’t. So recently the Garmin one just couldn’t provide data. I changed batteries, tried repairing, basically everything. So I was left trying to decide between dropping another $100 on a new strap or just use the Apple Watch and never get good data.
Then I was relaying this story to a friend and she flippantly pointed out how hairy my arms are and maybe I should shave. Now this got me thinking to the point to give it a go and what do you know - it works!
It makes sense really, as there was plenty of hair to remove and it would only block the sensor working.
So, if you have hairy arms, shave under your watch to get better and more accurate data.
PS after updating the same friend on the story, she told me she was only joking and had no basis to plant the seed.