VO2max is a measure for your personal capabilities and can be calculated based on a current (and good) race result. It can be used to get a prognosis for a half marathon based on your personal best for 10k or compare your personal bests of different distances.
In general, that's not sufficient. Runners want to know about their shape (i.e. optimal training paces and a prognosis for the upcoming race) while training for some event, not right after it.
Therefore, RUNALYZE estimates your current VO2max based on your activities. (Again: it's an estimation - not an exact calculation!) This estimation is based on your heart rate and your running pace. There are several studies for an approximate relation between heart rate and percentage of velocity at VO2max. Your current VO2max shape is based on the average of the last 30 days.
Still, this estimation is not that easy all the time. The maximal heart rate must be known and the heart rate graph of your activity must not go haywire due to a defect heart rate strap or other influences. RUNALYZE gives you the option to ignore an activity for your VO2max estimation (e.g. for activities with long pauses) to solve this problem.
In addition, everybody's heart rate may behave differently and does not need to follow the approximate equations. RUNALYZE uses an additional correction factor which is just multiplied with the calculated value. This factor is calculated based on your best race and its heart rate. If this factor does not fit for you, just pick a manual factor (Configuration -> General settings -> |VO2max|).
VO2max is a scientific metric for the maximal oxygen uptake that is highly correlated with your maximal running performance, but depends on the runners efficiency. Two runners with equal VO2max values do not need to perform equal. That's why we use the Effective |VO2max| that somehow ignores the efficiency and is equal for runners with same results for e.g. a 10k race. In addition to common calculators that estimate VO2max based on a race result, we estimate your VO2max for every activity based on the relation of your heart rate and pace.
Each VO2max value of an activity in RUNALYZE is marked with an arrow to show if this value is (much) higher than your current shape, equal to it or (much) lower.
Manual correction factor
If you think your VO2max correction factor, which is based on your best competition is not accurate, you can use a manual factor. Based on our experience, values between 0.85 and 0.95 seem to be realistic.
Adapt VO2max for elevation
If you run a lot up- and downhill, the effective work is more than the distance itself reflects. You can enable the adaption for elevation in the VO2max settings and set the correction (of the total distance) per positive and negative elevation.
Further readings and tools
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