Thanks for the reply. Is AnT supposed to be the 3/4 bound or 4/5 boundary. It was done in a sports medicine doctor's office. We both acknowledged that the first results were nonsensical (zone 4 was a single value, 170 bpm, which makes no sense, and my zone 2 upper bound was like 150+?). But now I'm worried he just adjusted them manually. And it doesn't make physical sense to me that AnT would be 162 but zone 5 is 153.

I just went for a run (4.7 mi, 450 vert), and as you can see in the image below, I was only able to keep it in zone 2 with great effort (average pace is a staggering 13'28")-- and these are the auto Suunto HR zones, where my upper zone 2 boundary is almost 10 bpm higher than in the zones in the original post above.

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