Understandable. I would flirt with the vivosmart 4 from Garmin, because it is waterproof. But even there, according to experiences on the web, only partially correct pulse readings can be expected. Please note that my experience is the only answer here. Maybe other people have had good experiences. It probably also depends on the type of sport and the intensity of exercise. I'll stick with the chest strap and Suunto for sport for my ambitions, but it's too clunky for everyday use. Good luck finding an alternative 🍀

I wore the watch over the winter for cross-country skiing and jogging. While my Suunto with chest strap measured an average pulse of around 165, the fitbit was around 120, or at most 140. In the case of the Engadine, the watch was in my jacket pocket and was able to measure a slightly elevated pulse. Fantastic performance 😄. Since then I leave the Fitbit at home when I do sport. Good recognition, however, when cycling. Jogging: the pulse rate is closer to the Suuntow value, but the difference is at least 10, often 20 beats/min.