Most runners and endurance athletes know that the higher your VO2 max, the better your cardiovascular fitness and the more “highly trained” you are from an aerobic exercise standpoint.
However, many athletes are not 100% sure exactly what VO2 max is or how to improve VO2 max. How is VO2 max calculated? More importantly, what can you do to increase your VO2 max?
In this article, we will discuss training tips for how to measure VO2 max and how to increase VO2 max for better athletic performance.
We will cover:
- What Is VO2 Max?
- How to Measure VO2 Max
- How to Increase VO2 Max
- How Long Does It Take to Improve Your VO2 Max?
Let’s get started!
What Is VO2 Max?
VO2 max, also known as maximum oxygen intake, is a metric that quantifies your aerobic capacity.
It refers to 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 intense exercise.
The units of VO2 max are milliliters per kilogram per minute (mL/kg/min). So, for example, if your VO2 max is 42 mL/kg/min, it means that when you are exercising at maximum aerobic capacity, your body can take in and use 42 mL of oxygen per kilogram of your body weight.
Your VO2 max quantifies the maximum rate at which you can take in oxygen (via the respiratory system), transport it to your muscles (through the circulatory system) and extract it from the blood, and use it efficiently for aerobic energy production (via aerobic metabolic pathways in the mitochondria in your muscles).
Thus, the higher your VO2 max, the more oxygen you can effectively take in and use during high-intensity exercise.
A high VO2 max theoretically enables you to produce more ATP (cellular energy) per minute so that your muscles can do more “work” or support faster running or higher-intensity exercise before crossing over your anaerobic threshold.
VO2 max is considered to be the gold standard measurement of aerobic fitness.
Because your VO2 max is a measure of how much oxygen you are able to take in and use during high-intensity exercise, it is a measure of your aerobic fitness or aerobic capacity (as aerobic means “with oxygen”).
How to Measure VO2 Max
So, exactly how is VO2 max calculated?
You can measure your VO2 max at an exercise physiology laboratory through a graded VO2 max test (usually on a treadmill or cycle ergometer).
However, there are also ways to estimate your VO2 max.
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.
Some premium running watches now have algorithms that can estimate your VO2 max based on your heart rate, pace, and relative effort level.
Examples include Garmin watches such as the Garmin Forerunner 45, 55, 245, 745, and 945, all Garmin Fenix watches, and Garmin Vivoactive 4/Venu watches have VO2 max, as does the Polar Pacer.
How to Increase VO2 Max
Even if you are not a competitive endurance athlete, increasing your VO2 max will help you improve your performance during all of your cardio workouts and will make aerobic exercise more comfortable at higher levels of intensity.
When you think about the elements that are involved in your VO2 max, there are essentially three arms:
- The amount of oxygen you can take in (which is essentially a product of your breathing efficiency)
- The amount of oxygen your heart can deliver to your muscles (which is dependent on how much blood your heart can pump per minute)
- The amount of oxygen your muscles can take up and use effectively to produce ATP through aerobic energy metabolism.
Therefore, if you want to improve your VO2 max, you can target any or all of these three factors in your training.
Here are some tips for how to improve VO2 max:
#1: Do High-Intensity Workouts
Whether you are primarily a runner, cyclist, or another type of endurance athlete, doing very high-intensity exercise, such as training at around 90 to 95% of your maximum heart rate, is a great way to strengthen your heart muscle and improve the efficiency of your cardiovascular system to deliver oxygenated blood to working muscles.
Of course, such high-intensity workouts should only be performed about once a week and in an interval-style workout, with recovery in between high-intensity bouts.
Examples of running workouts would be 10-12 x 400-meter repeats at 90 to 95% of your maximum heart rate or 6-10 600-meter repeats at a similar workload.
You can also do shorter repeats, such as 200 meters, at this effort level as you are building up the endurance to handle such a high intensity.
For cycling or other forms of aerobic exercise, you can do time-based high-intensity interval workouts. Again, shoot for that 90 to 95% of your maximum heart rate effort range.
Start with intervals of 30 seconds, and work your way up to two minutes or so.
Keep in mind that a full two minutes at 95% of your maximum heart rate may not be feasible, even for highly trained athletes. You will either need to drop the interval length to 90 seconds or reduce the intensity closer to 90%.
However, the primary goal should be to stay within that 90 to 95% of your max heart rate range, so it is better to shorten your intervals and maintain the desired intensity rather than push for longer at a slightly easier workload.
#2: Do Interval Workouts
Studies have found that interval training workouts are often slightly more effective at improving VO2 max than continuous aerobic exercise at a steady state.
Your VO2 max interval workouts can be run at a slightly lower intensity than the very high-intensity work just described.
For example, any interval-based workouts that are done at your VO2 max effort level or pace can help improve your VO2 max as a whole.
Variable-paced interval workouts can also be especially effective for increasing VO2 max.
Running at your VO2 max pace or exercising at an intensity level that correlates to your VO2 max improves the function of all three aspects (respiration, heart and circulation, and extraction and energy production).
#3: Do Long Runs
As much as it is important to incorporate interval training into your workout routine when you are trying to improve your aerobic capacity, endurance, steady-state workouts are also necessary.
Indeed, studies have found that training programs that incorporate both interval workouts, as well as steady-state efforts are the most effective way to improve VO2 max.
Continuous aerobic workouts condition your cardiovascular system by strengthening your heart and lungs and stimulating other favorable cardiovascular adaptations, such as increasing the elasticity of your blood vessels and the maintenance of a higher blood plasma volume.
Moreover, long runs and other long-endurance aerobic workouts help stimulate the production of new capillaries and mitochondria.
These adaptations, in turn, improve the oxygen uptake and aerobic energy production aspect of your VO2 max.
How Long Does It Take to Improve Your VO2 Max?
Many runners ask, “How long does it take to improve your VO2 max?“
The good news is that improvements in your VO2 max are possible at almost any fitness level or level of experience.
However, increasing your VO2 max is definitely a physiological variable that follows the law of diminishing returns.
In other words, the longer you have been consistently running or performing some type of aerobic exercise, and the fitter and higher your VO2 max is, the slower and less significant your improvements in VO2 max with training will be.
Beginners and untrained individuals can see pretty significant increases in VO2 max after just 4 to 6 weeks of training or so. Increases in VO2 max for highly-trained runners and endurance athletes are hard-won, and increases in VO2 max are typically on a much smaller scale, even with highly effective training methods.
This is largely due to the fact that some portion of your VO2 max is genetically determined, and there is a relative feeling for VO2 max for all humans, as well as for each individual, based on their own genetics and physiology.
To continue to make improvements in your VO2 max, you will need to increase the difficulty of your workouts, either by modulating the intensity itself, the distance or time for the intensity, the overall distance for mileage you are doing, and the frequency of your workouts.
Your cardiovascular system will adapt to the demands of your training program over time, so if you are not progressing in your workout program, you will hit a fitness plateau, and your improvements in VO2 max will stagnate.
To begin including some of these workouts into your training program, you will need to calculate your maximum heart rate and the rest of your heart rate zones. There are a few different ways to do so. If you would like to calculate yours, we have a helpful guide to help you here!