ErgData LogBook HR Zone Bands

[iain]

There will be a significant number of people where one or more of the formulae are close enough to be a useful guide. But there are also a lot who will vary so much that RPE is a far better starting point.

As someone whose fitness has varied many times, I have found that how my HR responds varies significantly. When unfit I can sustain 90+% HRmax for extended periods and need to do so as no significant exercise produces a steady HR any lower. I was very interested in a thread where consensus seemed to be that contrary to what I had believed HRmax is not constant but declines as stroke volume increases when the individual moves from untrained to trained. Not sure whether this means the 90% above was actually a lower proportion of a higher max. Certainly I have found in the first 6 weeks of training I usually hit what I believe to me my max a few times, but rarely get closer than 4 beats from this afterwards despite harder TTs over the range of distances. Should I lower my HRmax to that observed outside this initial period? If so I regularly hit 97-8% on hard sessions rather than the 96% I currently record.

More importantly I find that after a few months of training I find an HR that I assume is "threshold" where my HR traces hit an inflection, currently around 90% of my HRmax. This rises slightly with significant continued training. Personally I have no success investigating the UT2/UT1 divide for Zone 2. I fear that dehydration causes sufficient drift that this is difficult to determine and expect that a plateau would more likely show when I started sweating significantly (heavily influenced my temperature and humidity) rather than anything more meaningful. That said, to maintain 70% HRmax I need to row at >2k+45S. It isn't very stable, but there seems to be a bit of an inflection at about 77% HRMax which initially requires a pace around 2k+30-35S.