My zone is set by the 220 method that I got off a chart. My HR is from my Garmin. I realize there could be somewhat inaccurate but when I check it’s accuracy manually it’s for the Hr most part it’s pretty accurate. I had a standard stress test a few yrs ago and everything was fine. I had only 1 ride of that length this yr, and that was the one I was pretty tired after(upper legs). Most rides so far are in the 1:15-1:30
Last edited by justtrying; 05-21-19 at 08:37 AM.