Vital capacity

Vital capacity is a parameter for the function of the lungs, and is used in spirometry. There are sizes for each of the inhalation ( inspiratory vital capacity ) and for exhalation ( expiratory vital capacity). Respiration takes place through a mouthpiece, breathing through your nose should be prevented by a nose clip. The measurement accuracy depends not only on physical factors such as air pressure and turbulence, also on the cooperation of the subjects from which so each has a maximum inhale and exhale, which is certainly subjective.

One distinguishes the static vital capacity, which considers only the air volume of the lung itself, and the dynamic vital capacity, which takes into account the gas flow at inhalation and exhalation. Among the static parameters include the expiratory and inspiratory vital capacity. The dynamic characteristics include the forced vital capacity.

The desired values ​​of vital capacity are dependent on gender, age and body size. You can specify the following basic equations: where g with the body size is given in centimeters and a is the age in years.

Expiratory vital capacity

The expiratory vital capacity is the amount of air that can be exhaled in the strongest effort at once.

The measurement is usually done in three steps: