What is defined as the volume of air inhaled or exhaled during normal breathing?

Tidal volume is the volume of air that is inhaled or exhaled with each normal breath. In the context of physiology and respiratory function, it represents the amount of air exchanged during regular breathing cycles when a person is at rest, without any forced inhalation or exhalation. This value is important because it indicates the efficiency of the respiratory system and provides insight into lung function.

Understanding tidal volume is crucial in various clinical and athletic settings, as it helps assess respiratory health and can guide interventions in patients with respiratory conditions.

Vital capacity, on the other hand, refers to the maximum amount of air that can be exhaled after a maximal inhalation, and it combines several lung volumes, which makes it distinct from tidal volume. Expiratory reserve volume is the additional air that can be forcibly exhaled after the end of a normal exhalation, and inspiratory reserve volume refers to the additional air that can be inhaled after a normal inhalation. Both of these measurements contribute to understanding lung function but do not represent the air exchanged in normal breathing cycles like tidal volume does.