Discussion: HR

Sounds like maybe your heart strap was malfunctioning.

Also, what are your heart rate zone range limits?

Here's what I got from the 3K time trial:
Zone 0 - 0 bpm to 95 bpm
Zone 1 - 96 bpm to 114 bpm
Zone 2 - 115 bpm to 133 bpm
Zone 3 - 134 bpm to 152 bpm
Zone 4 - 153 bpm to 171 bpm
Zone 5 - 172 bpm to 192 bpm

Ok - those ranges feel off to me. I doubt your true max heart rate is 192. It's probably around 200 to 205.

The lower end of zone 5 is, depending on the definition anywhere from 180 ish to 195-200. All of the others will be higher as well. The bottom end of zone 1 should probably be more like 110 or even 120.

Ok, I've adjusted the HR zones to be:

Zone 0 - 0 to 120
Zone 1 - 121 to 136
Zone 2 - 137 to 152
Zone 3 - 153 to 168
Zone 4 - 169 to 184
Zone 5 - 185 to 200

How does that sound?

Yeah that seems a lot more realistic.

That should fix the zone 4/5 showing up in easier runs issue.

You may be a bit surprised by what is needed to get into zone 1 now but I think that's a good thing.