Vital capacity

Spirometry refers to the amount of gas that can be exhaled after the maximum inhalation and maximum exhalation under unlimited time. This represents the maximum functional activity of the lung at one time and is one of the important functional indicators reflecting the level of human growth and development. The "National Student Physical Health Standard" requires that vital capacity is a required test item for students in the fifth and sixth grades of elementary school, junior high school, high school, and university. Vital capacity is affected by age, gender, length, and body surface area. Vital capacity = tidal volume + supplemental inspiration volume + supplemental expiration volume. Tidal volume is the amount of gas inhaled or exhaled with each breath.