Each respiratory movement at rest is accompanied by the exchange of a relatively small volume of air - 500 ml. This volume of air is called respiratory. After completing a quiet breath, a person can take another breath, and another 1500 ml will enter the lungs - this is the so-called additional volume.
Similarly, after a simple exhalation, with effort, a person can exhale additional air in a volume of 1500 ml, which is called a reserve exhalation.
Vital capacity, spirometer
The total volume of the described values - breathing air, additional and reserve - in total equals an average of 3500 ml. Vital capacity is the volume of air exhaled after a forced inhalation and a deep exhalation. It can be measured with a spirometer - a special device. Lung capacity averages 3000-5000 ml.
Spirometer is a device that helps to measure the capacity and evaluate the ventilation of the lungs, taking into account the volume of forced exhalation after a deep breath. This device is best used in a seated position with the device vertical.
Vital capacity, determinedspirometer is an indicator of restrictive diseases (eg pulmonary fibrosis).
The device allows these diseases to be distinguished from disorders that cause airway obstruction (asthma, for example). The importance of this diagnosis is great, since the degree of development of diseases of this type is difficult to determine on the basis of clinical symptoms.
Breathing process
With calm breathing (inhalation), out of 500 ml of inhaled air, no more than 360 ml reaches the pulmonary alveoli, the rest is retained in the airways. Under the influence of work in the body, oxidative processes are intensified, and the amount of air is insufficient, i.e., the need for oxygen consumption and the release of carbon dioxide increases. The vital capacity of the lungs must be increased under these conditions. The body for normal pulmonary ventilation must increase the frequency of breathing and the volume of inhaled air. With a sharp increase in breathing, it becomes superficial, and only a small part of the air reaches the pulmonary alveoli. Deep breathing improves pulmonary ventilation and proper gas exchange occurs.
Prevention of lung diseases
Sufficient lung capacity is a very important factor that contributes to maintaining human he alth and good performance. A properly developed chest provides normal breathing to a certain extent, so morning exercises, sports, and physical education are very important. They contribute to the harmonious physical development of the body and chest as well.
The vital capacity of the lungs depends on the purity of the surrounding air. Fresh air has a positive effect on the body. On the contrary, the air in stuffy enclosed spaces, saturated with water vapor and carbon dioxide, has a negative effect on the breathing process. The same can be said about smoking, inhaling dust and polluted particles.
Remedial activities include greening cities and residential areas, asph alting and watering streets, installing smoke extractors on the exhaust pipes of enterprises, and absorbing ventilation devices in houses.
