Knowing your V02 max, or your aerobic capacity, is a valuable metric for both competitive and recreational athletes who want to assess their cardiovascular fitness, as well as sedentary individuals and the everyday population who want to understand their cardiovascular disease risk.
In this guide to how to measure VO2 max, we will discuss what V02 max is and how to test yours on your own outside of a lab.
We will look at:
- What Is VO2 Max?
- How Can I Test My VO2 Max?
Let’s get started!
What Is VO2 Max?
Aerobic capacity is measured by VO2 max, which refers to maximum oxygen uptake.
Also known as maximum oxygen intake, it is a metric that quantifies your aerobic capacity.
Your VO2 max denotes the maximum amount of oxygen (in milliliters of volume) that your body is able to use per minute per kilogram of body weight while running or performing some other form of vigorous cardio exercise.
VO2 max measurements use measurement units known as milliliters per kilogram per minute (mL/kg/min).
So, for example, if your VO2 max is 37 mL/kg/min, it means that when you are exercising at your maximum aerobic capacity, your body can take in and use 37 mL of oxygen per kilogram of your body weight per minute.
But, what factors actually go into your VO2 max score?
If you think about the various components of the cardiovascular system and aerobic metabolism—producing energy (ATP) aerobically (with oxygen)—there are several physiological components of cardiorespiratory fitness that influence this metric.
Again, VO2 max quantifies the maximum rate at which you can take in and use oxygen, so it looks at:- The ability to inhale oxygen (via the respiratory system)
- Transport oxygen to your muscles (through the heart and blood vessels or the circulatory system)
- Extract the oxygen efficiently from the blood at the muscle fiber and capillary interface level
- Use the extracted oxygen efficiently for aerobic energy production (via aerobic metabolic pathways in the mitochondria in your muscles).
Therefore, you need:
- Strong lungs with good tidal volume to take in a lot of oxygen
- A strong heart that can efficiently pump blood with a greater stroke volume per beat
- Elastic blood vessels that can handle a lot of blood
- Sufficient hemoglobin to carry the oxygen in the blood
- Ample capillaries surrounding all of your skeletal muscles used during exercise as if opening up more “roadways“ to bring oxygen to the muscles
- A high mitochondrial density in your type I muscle fibers so that you can produce lots of ATP through aerobic respiration simultaneously
- Trained muscles so that they require less oxygen/ATP at higher exertion rates because they are conditioned for the activity you are doing
Thus, the higher your VO2 max measurement, the better your aerobic capacity or aerobic fitness.
This is because a high VO2 max means that you are able to take in and use a lot of oxygen efficiently during high-intensity exercise without crossing over the anaerobic threshold, after which fatigue will rapidly ensue.
For this reason, it is considered to be the gold standard measurement of cardiorespiratory fitness or aerobic fitness.
As such, its measurements are particularly important for endurance athletes like distance runners, cyclists, endurance swimmers, long-distance hikers, and triathletes.
How Can I Test My VO2 Max?
The gold standard for measuring VO2 max requires going to an exercise physiology lab and using fancy metabolic equipment and specific protocols, which is generally not an accessible or affordable option for everyone.
The good news is that there are a few ways for how to test VO2 max on your own or at least get a good estimation of your measurement.
Exercise physiologists out of the University of Kent are credited with creating a DIY VO2-max test that is basically a self-paced running test you can do on your own.
This measurement is perhaps a bit more accurate than some of the VO2 max estimations or other ways for how to test at home, particularly if you are a runner, because it is said to replicate the demands of running a race well.
You will need a treadmill, a heart rate monitor, and someone to record your numbers.
The test will take 10 minutes once you get started.
There are five stages of this home assessment, each lasting two minutes.
The incline will stay the same throughout the duration of this protocol; only the speed that you run will change (if you need to in order to hit the required RPE used in this DIY VO2 max running test).
Rather than dictating a specific change in incline or treadmill speed, this VO2 max testing protocol is governed by your rate of perceived exertion, RPE, on a scale of 0 to 20.
Each stage has a specific effort level you should be running at, with the final stage being an all-out sprint effort for two minutes right from the beginning of that stage (8 minutes into this VO2 max test at home).
Here is what you will do:
- Warm up by jogging or walking.
- Set the treadmill to a 1% incline and keep it there.
- Then, here are the stages for how to test VO2 max on a treadmill with this running VO2 max testing protocol:
| Stage | Time | RPE | Exertion level |
| 1 | 0-2 mins | 11 | Light |
| 2 | 2-4 mins | 13 | Somewhat hard |
| 3 | 4-6 mins | 15 | Hard |
| 4 | 6-8 mins | 17 | Very hard |
| 5 | 8-10 mins | 20 | Maximum |
Then, heart rate and average running speed are charted to determine VO2 max.
There are a couple of useful pieces of information from this test for runners that are more practical than many of the other common ways for how to measure V02 max at home.
For one, you can get your maximum heart rate from whatever the highest heart rate you achieve during the final stage from your heart rate monitor data.
Most age-predicted maximum heart rate equations have a pretty large standard deviation or margin of error, so actually measuring your maximum heart rate can be helpful.
A lot of runners train by heart rate or use heart rate zones, so the more accurate you can be with knowing your maximum heart rate, the more accurate your training zones will be.
Secondly, this treadmill testing protocol also gives you vVO2 max, which stands for the velocity at your VO2 max. In other words, the running pace or running speed when you are running at VO2 max level.
Your VO2 max running pace is helpful for practical applications during workouts so that you know how fast you should be running for VO2 max workouts.
The average treadmill speed that you maintain or hit during the final stage of this test would be your vVO2 or VO2 max running speed.
There are other ways to test this important metric at home or outside of a lab, some of which may be more appropriate if you are not a runner or not able to exercise at a maximum intensity safely (or unsupervised safely).
Examples of VO2 max estimation protocols include the Rockport Walk Test, the 1.5-Mile Test, the Cooper VO2 Max Test, and the YMCA Cycle Ergometer Test.
Most of these can be done on your own; plus, because they are submaximal protocols for how to estimate VO2 max, they can be safer and easier for older adults, those with health conditions, or anyone who has a lower level of fitness.
There are also a variety of step tests, such as the Queens College step test or the YMCA step test.
However, these DIY tests require using steps of a specific height, so it can be difficult to do these at-home tests if you do not have the correct step size; using a step of a different size will produce inaccurate results.
Finally, higher-end running watches or GPS sports watches now have algorithms that estimate your VO2 max based on your heart rate, pace, and relative effort level.
For example, some of the best Garmin watches, such as the Garmin Forerunner 45, 55, 265, 745, 945, all Garmin Fenix watches, and Garmin Vivoactive 4/Venu watches have VO2 max, as does the Polar Pacer and new Polar Vantage 3.
I highly recommend the Garmin Forerunner 265 as the best GPS running watch for runners of most levels, from recreational runners to highly competitive runners.
The Garmin 265 GPS running watch measures VO2 max via Firstbeat Analytics along with other useful metrics such as running power, distance, speed, and everything you might imagine otherwise. It is nice and small (it actually comes in two watch face sizes)
A study that measured Garmin VO2 max accuracy found Garmin VO2 max estimated to be 95% correct, with a margin of error of less than 3.5ml/kg/min (which is equal to 1 MET).
This is quite reliable, and the Garmin VO2 accuracy is said to increase the most accurate you can be with your true max heart rate.
For another self-administered V02 max test, check out our guide to the Rockport Walk Test for VO2 max here.
