Those who engage with their own endurance will eventually come across VO₂max. Increasingly, the term is also heard in connection with Longevity. Especially Peter Attia has been a pioneer in this area. The higher, the better (or the older you get) - most people quickly realize this. But what is really behind the value - and what can you do to improve it?
What is VO2max?
VO₂max is arguably the most important measure of your aerobic performance capacity. It describes the maximum amount of oxygen that your body can take in, transport, and utilize during intense physical exertion. More specifically, it is the peak value of oxygen consumption per minute, usually relative to your body weight. It is expressed in milliliters of oxygen per minute (ml O2/min).
Why is oxygen so important?
Oxygen plays a crucial role in energy production. During physical activity, the energy needed for the muscles is provided by the biological combustion of oxygen. The more oxygen your body can absorb and utilize, the more efficient you are.
Importance of VO₂max
A high VO₂max is considered a sign of good endurance performance. However, it only reflects the upper limit of endurance performance - and is therefore often referred to as the gross criterion of endurance performance.
At the same time, a high VO₂max value does not necessarily mean that an athlete is better in a sport. Rather, other factors such as technique or mindset also play an important role.So don't be discouraged if your value is not yet in the supposedly "good" range.
The VO₂max is influenced not only by training and your lifestyle but also by your genetics. Some people naturally have a higher value than others - and thus possibly also a sporting advantage. Men usually have higher values than women.
How is VO2 max calculated?
VO₂max is a complex value determined by a combination of direct measurement and mathematical calculation.
1. Direct measurement in the laboratory
The most precise method for determining VO₂max is spiroergometry, a test usually conducted under medical supervision.The following parameters are recorded:
- Oxygen uptake (VO₂): The amount of oxygen your body takes in per minute from the inhaled air.
- Carbon dioxide output (VCO₂): The amount of carbon dioxide you exhale per minute.
- Tidal volume and respiratory rate: These values help analyze gas exchange in the lungs.
During a stress test on a treadmill or ergometer, the intensity increases continuously until you reach your maximum load limit. The VO₂max is measured precisely at the point where oxygen uptake does not increase further despite increasing load.
2.Calculation of VO₂max
VO₂max is calculated using the following formula:
VO2max = HMV x AVO2D
The heart minute volume (HMV) indicates how much blood is pumped through your circulation per minute. It is calculated based on your heart rate per minute and the stroke volume - that is, the amount of blood pumped per heartbeat.
HMV = HR x SV
AVO2D stands for the arteriovenous oxygen difference. The background: Oxygen-rich blood is transported through the arteries to the working muscles and metabolized in the muscle cells. The subsequently oxygen-poor blood is then transported back through the veins.
The AVO2D indicates how well your body is able to bind, transport, and utilize oxygen in the blood.
This means: The higher your heart rate, stroke volume, and arteriovenous oxygen difference, the higher your VO2max. These maximum values are reached under full load.
3. Alternative methods for estimating VO₂max
For individuals who do not have access to a laboratory, there are various tests to estimate VO₂max:
- Cooper test (12-minute run): The distance run is entered into a formula to estimate VO₂max.
- Astrand-Rhyming test: Here, the heart rate is measured during a submaximal exercise test on an ergometer.
Brand new is the "seismographic" measurement of VO2max. Here, a small, modified earthquake sensor is attached to your chest, and the value is determined without any physical exertion. The measurements have a very, very high correlation with the values obtained under exertion.
Absolute and relative VO2max
VO₂max can be expressed in two ways: absolute and relative. Because heavier athletes often have higher values than lighter athletes, in most cases, the relative VO₂max is calculated instead of the absolute - here, the weight is taken into account. This makes athletes more comparable within their discipline.
By the way: Your smartwatch usually also displays the relative VO₂max.
Absolute VO₂max
The absolute VO₂max indicates the total amount of oxygen that your body can take in per minute during maximum exertion. It is expressed in liters per minute (L/min).
Example:
A person with an absolute VO₂max of 4.0 L/min can take in and utilize 4 liters of oxygen per minute.
Relative VO₂max
The relative VO₂max incorporates body mass into the calculation and is expressed in milliliters of oxygen per kilogram of body weight per minute (ml/kg/min). It shows how efficiently your body can use oxygen in relation to your weight.
Formula:
Relative VO₂max = Absolute VO₂max (in ml/min) : Body weight (in kg)
Example:
A person with an absolute VO₂max of 4,000 ml/min and a body weight of 70 kg would have a relative VO₂max of 57.1 ml/kg/min.
Measuring VO2max: How reliable are heart rate monitors?
Most modern heart rate monitors and fitness trackers offer the ability to estimate VO₂max. They use algorithms that analyze data such as heart rate, movement, and sometimes also the oxygen content in the blood (via optical sensors).
How does the pulse watch estimate your VO2max?
The estimation of VO₂max is based on several factors, including:
- Heart rate: During a training session, the heart rate is related to the intensity of the load. A low pulse at high load indicates a high VO₂max.
- Resting heart rate: A low resting heart rate is often an indicator of good cardiovascular health and is included in the calculation.
- Activity data: Speed and distance covered, e.g., during a run, are used to assess fitness.
Some devices also take personal data such as age, gender, and weight into account to estimate VO₂max more accurately.
How accurate is it?
The accuracy of VO₂max values from heart rate monitors can vary significantly and often depends on the following factors:
- Quality of the sensor: High-quality devices from well-known manufacturers generally provide more precise values.
- Individual fitness level: In well-trained individuals, the values often deviate less than in beginners.
- Measurement conditions: Optimal conditions, such as a steady pace and stable heart rate, improve accuracy.
Limitations:
- Estimates are not individually validated: Algorithms are based on average values and do not take into account physiological peculiarities.
- Inaccuracies at submaximal load: The devices often struggle to provide precise values when you do not push yourself to your limits during training.
For an accurate value, you should always rely on spiroergometry or, more recently, the seismograph for the chest in case of doubt.
Fitness: What is a good VO2max value?
VO₂max is an important indicator of your endurance capacity. But what is actually a good value? The answer depends on various factors, such as your age, gender, and training level. Generally, the higher the VO₂max, the better your body is able to utilize oxygen during physical exertion.
Average VO₂max values by fitness level
Normal values / Recreational athletes:
Recreational athletes train regularly, but with moderate intensity. Their VO₂max is usually:
- Men: 35–45 ml/kg/min
- Women: 30–40 ml/kg/min
Aspiring athletes:
Aspiring athletes engage in structured training, often several times a week, and occasionally participate in competitions.Your values are mostly at:
- Men: 50–60 ml/kg/min
- Women: 45–55 ml/kg/min
Professional athletes:
Professional athletes achieve the highest VO₂max values through intense and continuous training. Depending on the sport, the values can vary significantly, especially in endurance sports such as running, cycling, or cross-country skiing:
- Men: 65–85 ml/kg/min
- Women: 55–70 ml/kg/min
- World class: up to 80 ml/kg/min
What VO₂max is considered "good"?
A VO₂max value is considered "good" if it is above the average for the respective age and gender group.Here are some reference values:
- Men (20–40 years): From 45 ml/kg/min upwards, the VO₂max is above average.
- Women (20–40 years): From 40 ml/kg/min upwards, the VO₂max is considered good.
Your VO₂max is a valuable indicator of your fitness, but it should always be considered in context. Whether you are a recreational athlete or a professional: improving your VO₂max requires targeted training.
Factors of a high VO2max
The VO₂max depends on various physiological factors. Each of these factors plays a crucial role in efficiently transporting oxygen from the outside world to the working muscles and converting it into energy.
High Capillarization
Capillaries are the smallest blood vessels in the body that deliver oxygen and nutrients directly to the muscle cells.
A high capillarization means that the muscles are particularly well supplied with blood. The more capillaries there are, the more efficiently oxygen can pass from the blood into the muscles. This improves oxygen supply during exertion and increases endurance performance.
Number of Mitochondria
Mitochondria are the "power plants" of the cells. Here, oxygen is used to produce energy in the form of ATP (adenosine triphosphate). The more mitochondria a muscle cell has, the more efficiently it can convert oxygen into energy. This means that your muscles can work longer without getting tired.
Our tip: This is how you can strengthen your mitochondria.
Cardiac output
Cardiac output indicates how much blood the heart pumps through the body per minute. It is the product of heart rate (beats per minute) and stroke volume (amount of blood per beat).
A high cardiac output means that more oxygen is transported to the muscles per minute. This allows the muscles to be sufficiently supplied even under high load.
Hemoglobin content
Hemoglobin is a protein in red blood cells that transports oxygen from the lungs to the muscles. A high hemoglobin content improves the oxygen transport capacity of the blood.More oxygen in the blood ensures that the muscles are better supplied and the VO₂max increases.
Lung function
The lungs are responsible for the intake of oxygen and the release of carbon dioxide. Maximum oxygen uptake begins with lung function.
It ensures that enough oxygen enters the blood. Factors such as vital capacity (maximum air volume that the lungs can hold) and diffusion capacity (efficiency of gas exchange in the alveoli) influence oxygen uptake.
VO2max and Longevity
VO2max plays a significant role not only in your athletic performance - your Longevity is also closely related to this value.Because even small improvements in VO2max positively affect your overall mortality risk, as a study showed.
Specifically, cardiorespiratory fitness is inversely proportional to long-term mortality, with no upper limit observed. This means: An extremely high aerobic fitness was also associated with the highest survival rate.
This effect is independent of age, gender, or origin. At the same time, increased cardiorespiratory fitness is also associated with numerous other health benefits, such as a reduction in coronary heart disease, high blood pressure, diabetes, stroke, and cancer.
How can you improve your VO2max?
Improving your aerobic performance is very individual. Therefore, there is not "one" way to a higher VO₂max.
Short intervals
What is that?
Short intervals consist of high-intensity exercise phases of 15–60 seconds, followed by active recovery phases.
Example:
- 8 x 30 seconds sprint (near maximum intensity)
- 90 seconds easy jogging or walking
Why is this effective?
Short intervals train your heart to transport oxygen quickly and efficiently to the muscles. They challenge your cardiovascular system to the maximum and improve oxygen transport capacity (cardiac output) as well as oxygen uptake in the muscles (capillarization).
Long intervals
What is it?
Long intervals last 3–8 minutes at 80–90% of maximum heart rate, followed by longer recovery phases.
Example:
- 4 x 5 minutes at high intensity
- 3 minutes of easy jogging or walking in between
Why is this effective?
Long intervals improve both your aerobic and anaerobic capacity. Your body learns to use oxygen more efficiently while simultaneously increasing the ability to metabolize lactate (lactic acid breakdown).
Hill sprints
What is it?
Hill sprints are short, high-intensity sprints (20–40 seconds) uphill, followed by easy jogging or walking downhill as recovery.
Example:
- 6 x 30 seconds sprint uphill
- 2–3 minutes of easy walking downhill
Why is this effective?
The additional gravity during uphill sprints challenges the muscles and the cardiovascular system extremely. The resistance trains your running-specific muscles while simultaneously improving the heart minute volume.
HIT Training
What is it?
HIT combines short, very intense exercise phases (85–100% of maximum heart rate) with short recovery phases. These sessions are similar to interval training, but usually shorter and more intense.
Example:
- 10 x 1 minute at maximum intensity
- 1 minute active recovery in between
Why is this effective?
HIIT increases both the maximum oxygen uptake and your body's ability to process oxygen quickly. At the same time, lactate tolerance is improved.
Slow, long units (Zone 1 & 2)
What is that?
Slow, long units consist of training sessions with moderate intensity over a longer period (60–120 minutes at 60–70% of maximum heart rate).
Example:
- 90 minutes of jogging or cycling at a relaxed pace
Why is this effective?
These sessions improve basic endurance and train fat metabolism. Additionally, they promote the capillarization of the muscles and increase the number of mitochondria.
