I've been using a 235 for at least five years now, and it works well for me. But I've got a question about the VO2 max reading.
I realize that it's not an accurate measurement in any absolute way. But I've found it helpful as a general assessment of my fitness. The highest reading I achieved was 51, several years ago towards the end of a spring training cycle, and at that point, age 60, I was able to run 7:38 pace in a 10K. After wrestling with injuries for the past year or so, I'm finally running--jogging--pain free again, and my VO2 reading, which went as low as 45, has stabilized at 46. I'm betting that with training and a few pounds lighter, I can get it up to at least 48, maybe 49. Again: just a relative marker of fitness, not an accurate absolute rendering. As I age, it's fun to play little data-games.
My question is how the 235 arrives at that VO2 calculation. I'm pretty sure that it's NOT based solely on the most recent run, but on an average of a certain number of recent runs: a trend line, as it were. It's almost as though it wants confirmation of increased fitness through several stronger-than-usual runs before it notches you up one number.
Can anybody answer this question? If it's an average, how many prior runs, along with today's run, does it sample?