Synonym
lactate certificate
Definition
Lactate performance diagnostics is a procedure that is primarily used when working with athletes. It is also used less frequently in everyday clinical practice. It is used to determine performance, especially in the area of endurance, for example in soccer.
It can also be used to check whether performance has increased or decreased over time. The basis of lactate performance diagnostics is the energy production of the muscle cells by aerobic and anaerobic means and the lactate formation, which gives an indication of the current mode of energy production. The body needs energy at all times.
During sustained physical exertion, it obtains a large part of this energy from the breakdown of sugars (carbohydrates) such as glucose. Glucose is available in a kind of storage form, glycogen, in muscle and liver. As long as the body is supplied with sufficient oxygen, the glucose obtained from glycogen is completely broken down into water (H2O), carbon dioxide (CO2) and energy in the form of adenosine triphosphate (ATP).
One speaks of aerobic energy production. Lactate is also produced in this area of energy production, but much less than in the area of anerobic energy production (see below). With increasing stress, the body is no longer able to provide sufficient oxygen for the energy metabolism at a certain point.
It must now produce the necessary energy without oxygen. For this purpose, glucose is also broken down from the glycogen, but not as completely as in the case of areobic energy production. Lactate and again adenosine triphosphate are formed.
In contrast to aerobic energy production, which produces a maximum of 38 mol ATP, anaerobic energy production produces only 2 mol ATP per molecule of glucose. Anaerobic energy production is therefore much less productive. However, its advantage is the independence from oxygen.
The lactate produced in large quantities during anaerobic energy production leads within a relatively short period of time to acidosis, the so-called acidosis. Such acidification leads to an inhibition of the processes responsible for glycogen degradation and the energy supply slowly comes to a standstill. For its own protection, the body is forced, so to speak, to stop the strain.
A distinction is therefore made between the aerobic and anaerobic areas in energy production. The point at which the body switches from one mode to the other is called the anaerobic threshold or lactate threshold. The intensity at which this threshold is reached depends very much on the training condition and is therefore very individual.
If the performance is below the anaerobic threshold, i.e. in the area of aerobic energy production, the athlete can continue to perform at this level for a relatively long period of time, for example a marathon runner. If the load is above the anaerobic threshold, i.e. in the area of anaerobic energy production, the body can only provide the performance for a short time, for example during a sprint. The anaerobic threshold is a lactate value of 4 mmol/l. However, this value is individually very variable and can only be considered as a rough guide value, which is why the term individual anaerobic threshold is used nowadays. The lactate concentration at rest is usually about 1-2 mmol/l.
All articles in this series: