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Calcimator

Altitude Performance Calculator

Performance decline from altitude and acclimatization.

Inputs

Results

Altitude VO2max

40.6

VO2max decline (%)9.8
Altitude pace (min/km)6.12
Pace slowdown (%)11.2
Time loss (min)6.2
Heart rate increase (%)15
Barometric pressure (kPa)70.1
Est. SpO2 (%)96
How to Use This Calculator
  1. Enter Sea-level VO2max (mL/kg/min), Event altitude (m), and Acclimatization days.
  2. Set Sea-level pace (min/km) and Race distance (km).
  3. Review the Altitude VO2max result.
  4. Use VO2max decline (%) and Altitude pace (min/km) to inform your decision.

How the result changes with Sea-level VO2max (mL/kg/min)

Sea-level VO2max (mL/kg/min)Altitude VO2max
2724.4
4540.6
6659.6
8374.9

What each input means

Sea-level VO2max (mL/kg/min)
Your VO2max measured at sea level.
Event altitude (m)
Altitude of the event in meters above sea level.
Acclimatization days
Days spent at altitude before the event.
Sea-level pace (min/km)
Your comfortable running pace at sea level.
Race distance (km)
Distance of the race or event.

What each result means

Altitude VO2max
Estimated VO2max at the given altitude after acclimatization.
VO2max decline (%)
Net percentage VO2max decline after acclimatization.
Altitude pace (min/km)
Expected running pace at altitude.
Pace slowdown (%)
How much slower your pace will be at altitude.
Time loss (min)
Extra time needed compared to sea-level performance.
Heart rate increase (%)
Expected resting/exercise heart rate increase at altitude.
Barometric pressure (kPa)
Atmospheric pressure at the given altitude.
Est. SpO2 (%)
Estimated blood oxygen saturation at altitude.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Sea-level VO2max (mL/kg/min) = 45, Event altitude (m) = 3000, Acclimatization days = 0, Sea-level pace (min/km) = 5.5 = 5 input(s) provided
  2. Calculate Altitude VO2max
    Altitude VO2max = seaLevelVO2max * (1 - netDeclinePct / 100)
    40.6 = 40.6
  3. Calculate VO2max decline
    9.8 = 9.8
  4. Calculate Altitude pace
    Altitude pace = seaLevelPaceMinPerKm * (1 + paceSlowdownPct / 100)
    6.12 = 6.12

Engine last updated .

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