As it became clear in the blog post on the factors of endurance performance, the maximum oxygen uptake (VO2max) is one of these crucial factors.
VO2max formally corresponds to the product of cardiac output (HMV), i.e. stroke volume (SV) multiplied by heart rate, and the arterio-venous oxygen difference.
VO2max = HMV * AVO2-D = SV * HF * AVO2-D
Maximum oxygen uptake is often referred to as oxidative capacity or gross criterion of endurance performance or cardio-pulmonary-metabolic capacity. As such, it encompasses all mechanisms involved in performance. Behind this is the body’s ability to produce energy in the form of ATP with the help of oxygen. As a reminder, ATP is the universal energy supplier of the cells. In other words, VO2max refers to the (maximum) flow rate (performance) of aerobic metabolism or oxidative phosphorylation. The value thus quantifies the maximum amount of oxygen that is inhaled per unit of time, diffuses through the lungs into the blood and reaches the active muscles via the bloodstream. There it is primarily used for aerobic energy production.
The level of VO2max is essentially dependent on the following factors:
- Oxygen diffusion capacity of the lungs
- Maximum cardiac output, i.e. pumping function of the heart
- Oxygen transport capacity of the blood
- Capillary and mitochondrial density of the muscles
- Enzyme activity in the target muscles
VO2max is considered a prognostic tool and is often used as a talent indicator for future endurance performance. However, especially in performance-homogeneous groups, as often found in competitive sports, this value only allows a rough assessment of the endurance training status.
Due to its great importance, VO2max should be a mandatory component of complete performance diagnostics in endurance sports. Ideally, diagnostics should be left to experts and carried out in a sport-specific and standardised manner. Only if various factors that potentially influence the result are kept constant, including the test protocol, preload and time of day, can the measured values be compared. Various options are available for the survey. Without going into detail about their strengths and weaknesses, these include, for example, mixed chamber systems, the Douglas bag principle or breath-by-breath methods. Regardless of the method, a test protocol is required that allows the aerobic system to be fully utilised in a period of time before the test is terminated due to other causes. As a rule, the absolute VO2max is given in ml, the relative VO2max therefore in ml/kg body weight.
Increasing VO2max through training
We will show you in further blog posts which training is recommended to increase VO2max.
e.g. Joyner, M.E. & Coyle, E.F. (2008). Endurance exercise performance: the physiology of champions. The Journal of Physiology, 586(1), 35-44.