VO₂ Max Field-Test Calculator
Estimate VO₂ max from the original Kline one-mile track-walk equation, with relative oxygen uptake and input sensitivity views.
Aerobic fitness estimates inputs
Your aerobic estimate
42.43 mL/kg/min · estimated VO₂ max
Original Kline absolute-uptake equation, converted to relative uptake
Full result table
| Walk time (min) | Absolute estimate (L/min) | Relative estimate (mL/kg/min) |
|---|---|---|
| 14 | 3.406355 | 45.418066 |
| 14.25 | 3.350355 | 44.671399 |
| 14.5 | 3.294355 | 43.924733 |
| 14.75 | 3.238355 | 43.178066 |
| 15 | 3.182355 | 42.431399 |
| 15.25 | 3.126355 | 41.684733 |
| 15.5 | 3.070355 | 40.938066 |
| 15.75 | 3.014355 | 40.191399 |
| 16 | 2.958355 | 39.444733 |
Original study: healthy adults ages 30–69 using fast one-mile track walks, not jogging or a treadmill substitute. Use the protocol heart-rate measure, not resting heart rate. No population fitness percentile is assigned. Sensitivity scenarios are arithmetic, not predicted training gains.
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How to use VO₂ Max Field-Test Calculator
- Enter results from a level one-mile track walk, performed as a walk rather than a run.
- The supported age range matches the 30–69-year study group.
- Absolute uptake is displayed in litres per minute, and relative uptake divides that value by your mass.
Worked example
At the male coefficient, age 40, 75 kg, 15 minutes and 130 bpm, the absolute estimate is 3.182355 L/min and the relative estimate is 42.431399 mL/kg/min.
Formula, accuracy & limitations
Kline absolute VO₂max (L/min) = 6.9652 + 0.0091 × weight(lb) − 0.0257 × age + 0.5955 × sex − 0.2240 × walk minutes − 0.0115 × fourth-quarter heart rate. Sex coefficient is 1 male, 0 female. Relative VO₂max = L/min × 1000 / kg. 1 lb = 0.45359237 kg.
Original study: healthy adults ages 30–69 using fast one-mile track walks, not jogging or a treadmill substitute. Use the protocol heart-rate measure, not resting heart rate. No population fitness percentile is assigned. Sensitivity scenarios are arithmetic, not predicted training gains.
These outputs use the stated model and your supplied inputs. A mathematically consistent model can still differ from personal measurements. Scenario curves and formula comparisons are not statistical confidence intervals.
Read the research and method reference ↗Use a matching walk protocol
Enter results from a level one-mile track walk, performed as a walk rather than a run. The original study included repeated fast walks and used the fourth-quarter heart rate. A casual stroll, different distance or treadmill protocol does not match this equation.
Check age, mass and heart-rate units
The supported age range matches the 30–69-year study group. Enter body mass in kilograms; conversion to pounds occurs inside the equation. Enter walk time in decimal minutes and the protocol heart rate in beats per minute. Resting heart rate is not a substitute.
Interpret the two oxygen numbers
Absolute uptake is displayed in litres per minute, and relative uptake divides that value by your mass. The time-sensitivity curve changes one input while holding the rest fixed. It is an illustration of the equation, not proof that a faster future walk will cause that exact physiological change.
Frequently asked questions
Is this the usual 132.853 Rockport equation?
This implementation uses the absolute-uptake equation printed in the original Kline study abstract, then converts to relative uptake. Coefficients from different equations are not mixed.
Can I enter a treadmill mile?
This page implements the track-walk equation. A treadmill walk has separate validation research and should not be silently treated as the same protocol.
Why is there no excellent or poor label?
A defensible category requires a clearly defined reference population and method. This tool reports the estimate without inventing percentiles.
What does the sensitivity curve mean?
It recalculates the equation at nearby walk times with age, mass and heart rate fixed. Those hypothetical combinations do not represent repeated physiological measurements.
