Tri-knowledge: VO2max explained clearly

What is VO2max exactly?

VO ₂ max is one of the most important indicators for evaluating aerobic performance. It indicates the maximum amount of oxygen the body can absorb and utilize under stress. The availability of oxygen is the central element in endurance performance - without oxygen, the muscles are only able to work for a few seconds, the aerobic energy metabolism determines the long-term performance in all disciplines. The VO ₂ max thus includes many physiological processes that describe the path of oxygen under stress:

• capacity of the lungs
• transport capacity in the blood
• muscular utilization and metabolism in the muscle cells.

Endurance training leads to adaptation processes in the cardiovascular system, i.e. to a higher level of functioning of the organs and processes. The totality of these processes is then expressed in the VO ₂ max value. The higher the value, the greater the aerobic capacity of the athlete, ie endurance performance can be maintained at a higher level of exertion over a longer period of time.

What does the abbreviation VO2max stand for?

VO ₂ max is an abbreviation – consisting of V for volume, O ₂ for oxygen and max for maximum: the body's maximum oxygen uptake. The number, which can often also be seen on your sports watch, describes the " relative VO2max ", because only this value ensures comparability between athletes:

rel. VO2max = mlO ₂ /min/kg , i.e. milliliters of oxygen per minute per kilogram of body weight. The volume is set in relation to the body weight, since more body mass also increases the absolute absorption capacity. Consequently, the relative VO ₂ max - not the absolute - is given as a standardization for better comparability and more meaningfulness with regard to endurance performance.

What is a good value for VO2max?

For "untrained" people, the average VO ₂ max is:

• Females ~ 35 mL/min/kg
• Men ~ 40 mL/min/kg

Endurance training causes VO ₂ max to improve significantly:

• Hobby and recreational athletes ~ 45 - 55 ml/min/kg
• performance-oriented amateurs > 55 ml/min/kg
• Competitive athletes ~ 65-80 ml/min/kg
• World class > 80 ml/min/kg

In women, these values ​​are about 10% lower overall.

How is VO2max calculated?

The VO ₂ max is calculated using the following formula:

_VO2max = HMV x _AVO2D

What sounds complicated is actually very simple . Cardiac minute volume (HMV) indicates how much blood is pumped through the circulatory system per minute. HMV is the product of heart rate (HR per minute) and stroke volume (SV), i.e. the amount of blood transported per heartbeat. So: HMV = HR x SV.

AVO ₂ D stands for the arteriovenous oxygen difference. To explain: The oxygen-rich blood gets through the arteries to the working muscles, the oxygen is metabolized there in the muscle cells, the "used up", oxygen-poor blood then flows back into the veins. The AVO ₂ D thus indicates how well the body is able to bind the "fresh" oxygen in the blood, transport it and convert it into the mitochondria (= power plants of the muscle cells). The greater the difference, the better the utilization of the existing O2 potential, the greater the arteriovenous difference.

For our VO ₂ max formula this means: the higher our heart rate, our stroke volume and our arteriovenous oxygen difference, the greater our VO ₂ max! These maximum values ​​are therefore reached under load.

How is VO2max measured?

Many heart rate monitors now have a VO2max display, but this is "only" calculated on the basis of the existing data (HF / HFvar). The more data (i.e. the more regularly recorded training units) the system has, the more precisely the value can be calculated. However, if you want to determine the VO ₂ max precisely, there is only one option: spirometry performance diagnostics. As part of a spiroergometry, the respiratory gases are measured and analyzed during a performance test. The diagnostics can be carried out sport-specifically for cycling or for running (note: VO ₂ max values ​​for cycling and running are usually not identical). In addition to measuring the VO ₂ max, statements can also be made about the aerobic and anaerobic energy metabolism, performance thresholds and other physiological stress parameters. This enables an exact determination of the individual training areas for cycling or running.

Why is that important?

As already described above, the goal of endurance training is to evoke adaptation processes in the cardiovascular system. Training areas serve to influence various functional processes in a targeted manner and to achieve specific adjustments: a long GA1 endurance run leads to different adjustments than intensive interval training in the development area.

In order to check the training progress, such a diagnosis can be repeated after approx. 10-12 weeks and the training values ​​are adjusted to the current level of performance.

Conclusion

The VO ₂ max describes the functional state of the body under endurance exercise, i.e. the aerobic performance in its entirety. A higher value therefore always means an improvement in this functional state. Through variable, targeted training, the oxygen-processing systems can be significantly optimized, which leads to a higher level of endurance overall.