I had a very similar experience. I did measure my heart rate previously though, and the high resting heart rate notifications were new. I was very worried at f

I had a very similar experience. I did measure my heart rate previously though, and the high resting heart rate notifications were new. I was very worried at first because one of my personally prioritized indicators of fitness was how quickly I could go from say, zone 3 to 50bpm. This was quite low, then suddenly I was having 70-90bpm around 30m after exercising. Yet it gradually went away and I never actually experienced discomfort or anything like it. I haven’t seen a high restating rate in around 6 months. I’d say it lasted around a year, in total. I can see why this condition could kill people with pre-existing heart issues or generally poor cardiovascular health. Having your heart working nearly double time at rest is a huge task when you’re already struggling. It was a great eye opener; I really don’t want to have this again and have it be the final straw that causes a heart attack.