There are many medical and non-medical reasons behind shortness of breath. Breathlessness may also be experienced when at altitude, or when the air quality is at dangerous levels, or when the temperature is very high or after a heavy workout.
There are a number of medical conditions that cause breathlessness in a person. Problems like allergies, asthma, heart disease, pulmonary disease, pneumonia, obesity, tuberculosis also cause shortness of breath.
Recently, it has also been said that COVID is affecting the breathing capacity of the patients. Many people who have typical COVID symptoms like sore throat, runny nose have also experienced breathing problems during the course of the infection.