Final answer:
During deep yoga breathing, tidal volume increases because you inhale more air than during normal breathing. Inspiratory and expiratory reserve volumes may decrease as a portion of their capacity is used during the deep breaths. Total lung capacity and residual volume remain unchanged.
Step-by-step explanation:
During a deep breath, such as those taken in yoga, several changes occur in respiratory volumes and lung capacity. The tidal volume (TV), which is the amount of air inspired and expired during normal breathing, increases as you take deeper breaths in and out. This heightened tidal volume results in an increased intake of air beyond the normal level of quiet breathing. Additionally, deep breathing can result in a decrease in the inspiratory reserve volume (IRV) since you are using some of that reserve to take the deep breath. The expiratory reserve volume (ERV) may decrease since you're exhaling more forcefully in the process of a deep yoga breath. However, the total lung capacity (TLC), which is the sum of the residual volume, expiratory reserve volume, tidal volume, and inspiratory reserve volume, remains constant, as it is the maximum volume of air the lungs can hold and it does not change with deep breathing. Lastly, the residual volume (RV), remains constant because it is the air that is always left in the lungs to prevent alveoli collapse and cannot be voluntarily altered by deep breathing.