What is "Firstbeat VO2Max est 95% accurate compared to laboratory measurements" mean?

Firstbeat, in its website, say the VO2Max estimation is 95% accurate compared to laboratory measurements. What does it mean?
If your fenix 5 shows VO2Max 50 ml/kg/min, so with laboratory measurement, it can be 47.5 to 52.5?
OR simply: in 100 peoples who has VO2Max 50 ml/kg/min in his fenix5, there are 5 peoples who does not have VO2Max 50?

0 Dr Phil over 8 years ago

+/- 5% of lab figure...I'd assume.

Better than putting a wet finger in the air and guessing though. It's only a number. While the number is useful, it's the trend over periods of weeks that re more important. If you undertake a bout of training for say 6 weeks targeting your VO2max it's the pre and post difference that matter. Too many people here are focussed on daily (meaningless) fluctuations.

0 diki. over 8 years ago

+/- 5% of lab figure...I'd assume.

Better than putting a wet finger in the air and guessing though. It's only a number. While the number is useful, it's the trend over periods of weeks that re more important. If you undertake a bout of training for say 6 weeks targeting your VO2max it's the pre and post difference that matter. Too many people here are focussed on daily (meaningless) fluctuations.

Good points. Hope it measure the trend correctly.
Hope not like this case: Your VO2Max estimate 49. Four weeks later 50, then another 4-weeks 51. Looking back, the first estimation was wrong, It supposed to be 51. Then actually, you are in the flat progression and the device just get it right after 8 weeks :)

0 mcalista over 8 years ago

Firstbeat talks about Mean Average Percentage Error. This means the estimate is wrong by 5% on average compared with lab estimates. So some people will have an error greater than 5%, and some people less.

The Firstbeat method accuracy improves from 9% to 5% error if your TRUE HRMax is used, rather than just an age-based estimate. So it is definitely worthwhile assessing your true maximum, rather than just using the 220 mnus age formula. Finding your max HR is hard, but involves nothing more sophisticated than running flat out up a hill.

Also, a new F5 has little data on which to form a baseline fitness assessment. Once you have a few weeks worth of workout data, its estimates become more accurate.