How to use the vo2 max estimator
- Pick the test you did: the 12 minute run, the one mile walk or the resting and maximum heart rate method.
- For the run, enter the distance you covered in 12 minutes in miles or meters. For the walk, enter age, weight, sex, mile time and the heart rate at the end. For the heart rate method, enter your maximum and resting heart rates.
- Read the estimate in mL of oxygen per kg of body weight per minute, with its value in METs.
- Treat it as a rough guide and repeat the same test later to see your own trend.
Formula
Cooper 12 minute run: VO2 max = (distance in meters - 504.9) / 44.73
Rockport mile walk: 132.853 - 0.0769 x weight (lb) - 0.3877 x age - 3.2649 x time (min) - 0.1565 x heart rate + 6.315 if male
Heart rate ratio: VO2 max = 15.3 x maximum heart rate / resting heart rate
1 MET = 3.5 mL/kg/min
The formulas are published estimates and were fitted to particular groups of people. They are not a replacement for a laboratory test in which oxygen use is measured directly.
Worked example
Running 1.5 miles (2,414 meters) in 12 minutes gives (2,414.0 - 504.9) / 44.73 = 42.7 mL/kg/min, which is about 12.2 METs.
A 40 year old man who weighs 180 lb walks a mile in 15 minutes 30 seconds with a heart rate of 140 at the end. The formula gives 132.853 - 13.842 - 15.508 - 50.606 - 21.910 + 6.315 = 37.3 mL/kg/min. A woman with identical numbers scores 31.0, because the male constant of 6.315 is left out.
With a maximum heart rate of 190 and a resting rate of 60, the ratio method gives 15.3 x 190 / 60 = 48.5 mL/kg/min.
What VO2 max is
VO2 max is the greatest rate at which your body can take in and use oxygen during hard exercise. It is shown as milliliters of oxygen per kilogram of body weight per minute. It is often used as a measure of aerobic fitness, and it tends to be higher in people who train regularly and to fall with age.
A direct measurement uses a mask and a graded test to exhaustion in a lab. The estimates here are cheaper and easier but less accurate, and they are best used to follow your own progress with the same test over time.
How to run the tests safely
These tests are demanding. Talk with a doctor before an all-out effort if you are new to exercise, have a heart or lung condition, take medication or are unsure.
- Warm up first and test on a flat track or route you can measure.
- For the 12 minute run, cover as much distance as you can at an even pace.
- For the walk test, walk a mile as fast as you can without running and count your pulse for a full minute at the end.
- Do not use the heart rate ratio with a guess for maximum heart rate. Age formulas for maximum heart rate carry large errors.
Assumptions and limits
- This is an estimate for general information only. It is not medical advice and it is not a diagnosis.
- The Rockport formula was developed for adults of roughly 30 to 69 years old. The tool warns outside that range.
- The 15.3 constant in the heart rate method comes from studies of well-trained men and can be off for others.
- The calculator does not label your result as good or poor, because published ranges depend on age, sex and the source.
Frequently asked questions
How do I calculate VO2 max without a lab?
Field tests such as the Cooper 12 minute run, the Rockport mile walk or the heart rate ratio give estimates. They are less accurate than lab measurement but can be repeated to track changes in your fitness.
What is a good VO2 max?
It depends on age, sex and training, and different charts give different ranges. Rather than judging one number, compare your results over time using the same test. A doctor or coach can tell you what is reasonable for you.
Is the Cooper test accurate?
It correlates well with lab values for people who pace the run well, but the estimate can be off by several points. It works best for people who are used to running and can judge an even pace.
How can I improve my VO2 max?
Regular aerobic training, including some harder intervals, tends to raise it, and gains are usually largest for people who are starting from a lower level. Build up gradually and ask a doctor about any health concerns first.