Why does vital capacity gradually decrease with age?
Vital capacity decreases with age due to changes in lung elasticity, chest wall compliance, and muscle strength. These changes can lead to a decrease in the ability of the lungs to stretch and fill with air, resulting in a reduced amount of air that can be exhaled after a maximal inhalation. Additionally, age-related factors such as decreased respiratory muscle strength and changes in lung structure can further contribute to the decline in vital capacity.