<unk>  and lung capacities refer to the<unk> of air in the lungs at different phases of the respiratory cycle. The average total lung capacity of an adult human male is about 6 litres of air. Tidal breathing is normal, resting breathing; the tidal<unk> is the<unk> of air that is inhaled or exhaled in only a single such breath. The average human respiratory rate is 30–60 breaths per minute at birth, decreasing to 12–20 breaths per minute in adults.
Lung volumes
Lung compliance
Ventilatory threshold
FEV1/FVC ratio
Tidal volume
Vital capacity
Peak expiratory flow
Peak inspiratory pressure