Recently I bought a new heart rate strap. I have owned a number of Garmin straps, but they all break down when changing batteries, even when replacing the rubber o-ring. There's much to say about that, but let's just leave at the fact that I was fed up with that. As always, I checked many reviews, including DCRainmaker, of course.
In the end, I opted for what many hail as the most accurate heart rate strap, namely the Polar H10. I was, therefore, very unpleasantly surprised that it really didn't work that well. Specifically, going for a run meant having around 3K's of extremely low heart rates. I did all the manual asked of me – yes, I really did read it – and that was exactly the problem.
The problem was that all strap manual ask you to moisten the pads that go on your skin, but I found a YouTube video (see below) that shows how wrong that advice is.
The drops of water have already left the pads, because those are very smooth and slippery. As the video will show you, it is much better to moisten your skin a bit and then properly put the dry strap on. I've tried it, and now the strap works absolutely fine. Thank you, Tom Tech!