Originally Posted by
Lemond1985
What I did was, I just found a long climb, got fully warmed-up, loose, and pain-free. Dropped it into the big ring on the climb and just rode absolutely as hard as hard as I could for 30 seconds or so, and could not go any longer, slowed down a couple seconds, went for it again. And again and again, maybe five or six times, until complete muscle and breathing failure and could not go another inch, even to save my own life. I watched the HRM and few seconds after that is when I got my personal highest all-time reading. So I would guess that's gotta be something close to my max.
I would go with this method.
I used the conventional wisdom of obtaining my MHR and I feel like I'm going to explode while in "my" Zone 4. Obviously I need to re-calibrate. Honestly, I use it mostly to keep track of my HR and not as an indicator of my fitness level or a metric that I track.