How is breathing rate defined?

Breathing rate is defined as the number of breaths taken per minute. This measurement is essential for understanding how well the respiratory system is functioning during rest and exercise. As physical activity increases, the body requires more oxygen, which raises the breathing rate to meet this demand. The breaths per minute give a direct indication of how efficiently the body is exchanging gases – taking in oxygen and expelling carbon dioxide.

In contrast, the amount of air held in the lungs refers to lung capacity, which is a different aspect of respiratory function. The volume of air exchanged during exercise pertains to tidal volume and other respiratory volumes, rather than the rate of breathing. The tempo of inhalation and exhalation, while related to the rhythm of breathing, does not specifically quantify how many breaths occur within a minute, which is the key aspect of the definition. Thus, the definition that accurately captures the essence of breathing rate is the number of breaths taken per minute.