Large Capacity, Less Volume

Lung capacity is the amount of air each lung can hold: approximately 5 liters in an adult, although it varies depending on age and height. However, this amount is not typically inhaled or exhaled. Indeed, when you are not doing physical work, for example, reading, breathing is almost imperceptible, and the amount of air inhaled and exhaled does not exceed 0.5 liters. When walking, this amount increases to 1 liter, and when playing - from 1.5 to 2 liters. This amount of air coming in and out is called the tidal volume.

The air in the lungs is never completely renewed, because there is always a reserve in the alveoli - a residual volume. Therefore, the total capacity of the lungs is the amount of air that enters them as a result of a deep breath plus the residual volume. Thus, the lung capacity is greater than the volume of air inhaled and exhaled at rest or during moderate exercise.