Vital capacity : (V.C) It is the total volume of air that can be expelled from the lungs after first filling the lungs to the maximum and then exhaling the same to the maximum :
VC = TV + IRV + ERV
= 500 + 2000 to 2500 + 1000 to 1500 = 3500 to 4500 ml.
Significance of V.C. : Vital capacity of a person gives important clues for diagnosing a lung problem. Measurement of this capacity helps the doctor to decide about the possible causes of the diseases and about the line of treatment. It determines the stamina of sportsmen and mountain climbers. The greater the vital capacity more is energy available to body. Sportsperson or mountain dwellers have higher vital capacity. Young persons have more vital capacity than aged.