Breathe better after a chest cold, flu, pneumonia, or COVID

Sometimes mucus secretions in the lungs can persist after someone starts to get better from a chest cold, flu, pneumonia, or COVID. To cope with the problem, experts recommend two approaches. One is doing exercises that clear the lungs, such as a series of breaths and coughs that dislodges mucus. The other approach is doing exercises that strengthen respiratory muscles. An example is diaphragmatic breathing, a type of deep breathing that relies on the diaphragm muscle located below the lungs.