Tracking fitness data is key for assessing your health, designing the right training program for your goals, and gauging your progress throughout your training routine.

When it comes to measuring aerobic fitness, VO2 max testing is the best way to determine the conditioning level of your cardiovascular system.

This is important for people participating in aerobic endurance-related sports as well as recreational athletes and fitness enthusiasts looking for measurable improvements in their cardiovascular performance.

This article discusses everything you need to know about testing your VO2 max, as well as some tips for improving your VO2 max once you have your baseline.

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VO2 max is the maximum rate of oxygen your body can use when exercising at maximum intensities.

When you surpass your VO2 max during cardio exercise, your body begins using anaerobic energy systems, which are much quicker to fatigue and cause a buildup of lactate in your muscles.

This ultimately coincides with the “burn” feeling you get when exercising at great intensity.

A higher VO2 max means you can exercise at a greater absolute intensity before relying on anaerobic energy systems. This exercise intensity level is also known as your lactate threshold or anaerobic threshold.

As a health indicator, VO2 max is a reliable measure of aerobic fitness and a key physiological measure of health in the adult population (1).

VO2 max measures your body’s ability to use oxygen. A higher VO2 max means a more conditioned aerobic system and indicates cardiovascular health.

Summary

VO2 max measures your body’s ability to use oxygen. A higher VO2 max means a more conditioned aerobic system and indicates cardiovascular health.

During a traditional cycle-ergometer VO2 max test, you exercise on a special stationary cycle at progressively greater intensities while wearing a mask hooked up to a machine.

The machine measures the amount of oxygen in the air you exhale compared to amount of oxygen you inhale. A bigger difference between oxygen level in the inhaled versus exhaled air means you have a higher VO2 max than someone who exhales a greater amount of oxygen.

During this process, your heart rate is also monitored. The test duration varies for each person, because the intensity increases until you reach the point of maximum oxygen consumption.

Once you hit your VO2 max, your body can no longer use the additional oxygen and switches to anaerobic energy sources, thereby limiting the time you can spend at that intensity.

The specific procedure is as follows (2):

  1. Electrodes and a blood pressure cuff will be placed on your body to monitor heart activity.
  2. You will apply a mouthpiece for the testing device. Your nose will be pinched, so you can breathe only through your mouth (unless the mask covers your entire face, which it may, depending on the facility).
  3. You will begin pedaling on a stationary bike while breathing into the mouthpiece of the device.
  4. Once you begin cycling, the difficulty will increase until you can no longer continue.
  5. The test typically lasts 8–12 minutes, depending on your fitness level.
  6. A catheter may be placed in your arm to draw blood and test for lactate levels throughout the process — you can typically opt out of this if needles are an issue.

At least one trained professional will always be present during the test to monitor and record as needed.

Maximal intensity cycle ergometer testing is considered the “gold standard” for VO2 max testing, meaning that any other VO2 max test methods are compared against this test to determine their relative VO2 max prediction accuracy.

Summary

Cycle ergometry is the gold standard for VO2 max testing and measures your inhaled and exhaled oxygen during maximal exercise.

VO2 max testing requires expensive testing equipment and trained supervisors to oversee the people being tested.

As such, performing the gold standard VO2 max test on your own is difficult or impossible.

Many cities have facilities where you can pay to have your VO2 max tested.

Prices vary substantially, depending on the location and the specific facility. However, you can expect to spend anywhere from $150–$250 for a VO2 max test in the United States.

Doing an internet search for VO2 max testing near you is a good place to start.

Additionally, you can search for higher end gyms in your area, which may offer this test as part of an intake process.

You can also ask local trainers, endurance athletes, or other fitness enthusiasts in your community if they can refer you to a testing location.

Summary

VO2 max tests typically cost $150–$250 and are available in most major cities. Performing an internet search and asking around in your area are good ways to find a testing facility.

Although you cannot perform a gold standard test, there are a few ways to estimate your VO2 max without access to lab testing.

The most common methods are known as submaximal tests because they do not require you to reach maximal intensity. This can be safer for certain clinical populations (1).

Recent research suggests that the fixed-rate single-step test is a reliable predictor of VO2 max (3).

During this test, you take steps up and down at a specific pace while measuring your heart rate and then run the results through a calculator such as this one.

The test length ranges from 3–5 minutes.

While more convenient than cycle ergometry, these methods do require you to measure your heart rate throughout the test. You will need access to a smartwatch or other tracking device, although you can theoretically take your pulse manually instead.

It’s also difficult to perform the calculations without a programmed calculator.

Some watches and fitness trackers have the built-in capability to run the calculations for you, which is very convenient.

Additional VO2 max estimation methods include:

  • resting heart rate
  • 1-mile walk time
  • 6-minute walk distance (4)
  • 1.5-mile run time

In all cases, these tests provide only an estimate of VO2 max. You will need to plug the values into a calculator programmed for the relevant formula.

If you cannot perform any of the above tests, it may be helpful to note that your resting heart rate and VO2 max are significantly correlated, according to a 16-year study on all-cause mortality (5).

This suggests that using your resting heart rate is a good substitute for VO2 max testing in terms of aerobic fitness. Resting heart rate is much easier to measure, so consider using this if the other methods are not an option.

Summary

Methods to estimate VO2 max without major equipment involve heart rate measurements and calculations during various exercise protocols. In the absence of any other data, measuring resting heart rate is a good substitute for VO2 max.

The general risks of VO2 max testing include (2):

  • fatigue
  • muscle soreness
  • irregular heartbeat
  • chest pain
  • sudden heart attack

To minimize the risk as much as possible, a trained exercise physiologist should oversee your VO2 max test. Testing in a facility means someone will be monitoring you for any red flags as the test progresses.

Although healthy people are at low risk, always consult a healthcare professional before attempting a VO2 max test, especially at home.

Summary

Some risks are associated with VO2 max testing. Consult a healthcare professional and seek guidance from an exercise physiologist before attempting a VO2 max test.

There’s no set frequency recommendation for VO2 max testing. However, research shows that improvements to VO2 max in response to training can occur in as little as 10 weeks (6).

With that in mind, if you’re following a cardiorespiratory training program, testing VO2 max every 10 weeks or so is not unreasonable.

However, if time and budget constraints do not allow for this testing frequency, there’s nothing wrong with performing VO2 max tests every 6 months or even longer.

Just know that to measure the result of a specific workout program, you’ll need you to test soon after the program ends, as being sedentary will negatively impact your improvements.

Summary

There’s no hard-and-fast rule for how often you should test your VO2 max. When training for cardiorespiratory fitness, you may start to see improvements in VO2 max after 10 weeks.

General aerobic training, performed multiple times per week, is effective at improving VO2 max over time.

One of the most effective protocols for VO2 max improvement is high intensity interval training (HIIT). Because HIIT requires less time than steady-state endurance workouts, many people tout its benefits. Still, both HIIT and endurance training will improve your VO2 max (7).

As a rule of thumb, your best bet for improving your VO2 max is training slightly below, at, or slightly above your current VO2 max.

If your perceived intensity is very high and you’re gasping for breath, you’re at the point of pushing into your anaerobic threshold.

This is the zone you should be aiming for during the high intensity portions of your workout.

If you cannot exercise at near-maximal intensity, performing longer duration cardio is your next best bet.

To summarize, you can do the following to improve your VO2 max:

  • Perform aerobic exercise at least twice per week.
  • Alternate high intensity and low intensity intervals for maximal improvement.
  • Aim to push your lactate threshold if possible — in other words, “feel the burn.”
Summary

High intensity intervals are the best way to improve VO2 max, but long steady-state cardiovascular exercise will also yield improvements.

VO2 max is an important measure of aerobic fitness and general health.

Whether you’re seeking improved performance or better cardiovascular health, testing your VO2 max will give you a baseline to measure future fitness improvements and assess your current aerobic health.

Cycle ergometry in a lab setting is the gold standard method for measuring VO2 max.

If you do not have access to this equipment or a lab, you can get a decent approximation of your VO2 max using other methods.

You can most effectively improve your VO2 max by performing high intensity interval training several times per week.

If you cannot exercise at that intensity for health reasons, do not worry. Performing longer duration, lower intensity cardio is still very beneficial and will improve your VO2 max.

Regardless of how you measure, estimate, or improve your VO2 max, aiming to increase this important threshold will only make you stronger and healthier overall.