Global organ systems

During sporting activities, the body is able to set the organ system to performance mode and then switch to regeneration mode. In addition to food intake, the cardiopulmonary system is particularly important for enabling physical exertion, as oxygen is needed to provide energy.

Respiratory and transport system

The transport of oxygen and the removal of CO₂ is ensured via the bloodstream. A distinction is made between internal and external respiration during oxygen uptake. External respiration takes place in the lungs and is responsible for absorbing oxygen from the ambient air. At the same time, the body's CO₂ is released. Internal respiration, also known as tissue respiration, involves gas exchange in the cells of the body.

Lungs

The lungs and their components are responsible for external respiration. In performance diagnostics, the measurement of lung volume, oxygen uptake capacity and also the components of the exhaled air are of interest. An increase in lung volume as a result of training has not yet been demonstrated, which is why lung volume should be regarded as a limiting factor for athletic performance. However, training can improve the respiratory muscles, which helps to better utilise the available lung volume.

Blood

Blood is responsible for transporting the oxygen absorbed through external respiration and the CO₂ produced during energy production. More precisely, the red blood cells, which are able to bind the two gases to themselves. Every person has between 4-7 litres of blood in their body, 99% of which consists of red blood cells. The proportion of solid components in the blood is known as the haematocrit and a value of 42% is considered normal. However, this value can be increased to up to 55% (e.g. through altitude training), which increases the transport capacity of the blood. However, such a high haematocrit makes the blood thicker and increases the risk of heart attack and thrombosis. In addition to transporting oxygen, the blood is also responsible for the immune system and the transport of hormones, nutrients and other important substances.

The haematocrit can be increased illegally through blood doping or EPO. It should be noted that EPO is not illegal in itself, but is the body's own hormone that stimulates the production of red blood cells. However, it can also be administered to the body from outside, which is illegal for athletes according to the WADA Code.

Heart and vascular systems

The heart pumps blood to the cells in the body. The heart consists of two systems, one connected to the lungs and the other to the whole body. The pulmonary system pumps deoxygenated and CO₂-containing blood into the blood vessels of the lungs. This is where the gas exchange takes place and the oxygen-rich blood returns to the heart, where it is pumped by the second system into the aorta (main artery) and then distributed throughout the body via the many branching blood vessels. Once the oxygen has been delivered to the cells, the blood flows back to the heart and is pumped back into the vessels of the lungs. At rest, the heart achieves a pumping volume of 5-6 litres per minute. It is possible to improve the heart's pumping volume through training. Under stress, a minute volume of 22 litres (untrained person) to over 40 litres (trained person) can be achieved. An athlete's heart reaches a weight of 350-500g with a volume of 1500ml, while an untrained heart weighs only 250-300g.

With regard to heart rate, it should be noted that there are large individual differences and that the maximum heart rate decreases with age (5-10 beats per 10 years).

More info:

• Training explained - Handbook of training theory (Jost Hegner):

  • Global organ systems