Originally Posted by
GhostRider62
Fair enough, you don't know.
Here are some facts, I went from a recumbent with a CdA of around 0.160 m^2 to an upright with CdA of around 0.360 m^2 during which time my VO2 max power increased 46 watts. Logic would say my VO2 max increased during that time. Yet, my Garmin reported a decrease from 73 to 61 ml/kg.
What other explanation is there that firstbeatoff uses anything other than speed and HR as the primary determinants of VO2 max? Read the patent.
Your heart rate was different. That would explain what you saw entirely. I understand that you think you have a good guess, I just told you how to prove it disprove it.