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Race prediction times not accurate when compared with VO2 Max.

Hi, my FR 945 measures my VO2 Max as 62, with the following race predictions:

- 5K: 17:20

- 10K: 36:32

- Half: 1:20:58

- Full: 2:53:53

I don't think these times are correct for a person with VO2 Max of 62.

F.e. if you look up Jack Daniels' Table: these are the estimated times for VDOT 62:

62 4:27 4:49 9:33 10:18 16:34 34:23 52:47 1:15:57 2:38:54

Any advice?

  • The race predictor is not only based on your VO2 max but on a First Beat algorythm. Therefore there might be some difference !

  • Possibly, but I think the difference is really too big. And I actually ran a 15:50 5K on track 1 month ago, and because Garmin always measures too much distance on a track, I even had a 15:00 5K (because the FR 945 measured 5,3K).

    So even VO2 Max seems to be an underestimation.

  • Your training level is obviously pretty good. I think you should do a professional diagnostic anyway. 

    Curious how this will compare with Garmin or the Daniels table. 

  • Typically fitness based vo2max charts are way off, because they are looking at your current vo2max value... then assuming if you ran 70-100miles per week, elite training... what that would then give you as a race time.  HOWEVER, your vo2max would likely rise if you trained at that level!!  So a bit of a chasing your tail situation.  vo2 has a lot of genetic component, you could have a high vo2... but very poor lactate processing to run a hard 10k or aerobic/fat burning ability to complete a marathon, etc... its just one component.   My vo2 is 64/65 based on strong 15-25minute threshold run workouts... but I am NO WHERE NEAR those projected race times, and vdot gives me just a 54/55 on my actual race times!!!  

    I really don't know what the real point of them is?!  Being that the race time predictors, plug in a race time or time trial... get other race results... are pretty darn spot on (but again, assuming correct&strong training).  More accurate for shorter races and races of similar distance.  

  • I don't think these times are correct for a person with VO2 Max of 62.

    VO2max is only a measure of how your body utilizes oxygen for energy. It is not a measure of how well your muscles can turn that energy Into performance. That is why people with equal VO2max results can and do produce different outcomes.

    These predictions are based on empirical research and provide an estimate not a statement of fact that you will achieve the times.

  • The race predictor takes into account your recent running history. If you haven't been doing a lot of distance work recently, the predictions for half and full marathon distances in particular will extend compared to someone with the same VO2Max who has been doing distance work.

  • I’d post this on First Beat social media too and you might get a detailed response. About 2 min difference for a 5km at local champion level is a lot. Could be a case of an inaccurate Max HR? You’ve got more in the tank than your watch thinks. 

    How are the 10K and above times? Realistic or soft It could be that your ideally suited to 5K and below. 

  • Recent 10K of 33:40, so about 3 minutes off.

    Haven't run a half or full as race in quite a while, so can't compare these.

  • Well easy, run half or full and then you know which one is more wrong the tables or the Firstbeat's algorithm! :) 

  • Very strange to see the Garmin Race Prediction be SLOW, usually it is a good bit faster!  So that means that points to a vo2max is higher than 62 most likely.  Or.... you have a Pro level running economy and lactate threshold (among other attributes)!!!

    I would do some hard diggin through race data, super hard longer intervals, etc to make sure you maximum HR is legit.  Should be determined by a workout/race that you damn near blacked out!!!   Otherwise (for example) your watch thinks you are gassed at 94% max HR towards the end of a threshold run... when in reality you were only cruising along at a sustainable 86%.  Thinks you are a 62... when in reality you are a 64+.  

    My watch thinks i'm a 17:02 5k'r (64 vo2)... i'm NOT (@5:28, that is almost my 1mile pace of 5:23!)  !  I just have the base aerobic and low HR training, to keep HR very low on LT workouts.