- Initiation of Exercise: At the initiation of exercise, the respiratory frequency increases rapidly. The abrupt increase in breathing is due to neural changes that send excitatory impulses to the dorsal respiratory group (DRG) of the medullary respiratory center in the medulla.
- Moderate Exercise: During moderate exercise, the muscles need to work harder; thus, more oxygen should be produced, and more carbon dioxide is produced. As a result, the depth and rate of breathing increase to meet the body's needs.
- Asthma Attack: In an asthma attack, the airways become obstructed after exposure to a certain trigger, which then causes breathing to become harder as the air gets trapped in the lungs.
- Abrupt Ascent into High Altitudes: The air at higher altitudes is colder, less dense, and contains fewer oxygen molecules. As a result, breathing becomes more difficult and you'll need to take more breaths in order to get the same amount of oxygen as you would at lower altitudes.
- Pneumonia: Pneumonia is an acute infection or inflammation that causes the alveoli to become inflamed and filled with fluid or pus. It interferes with ventilation and gas exchange and makes breathing harder for infected individuals.
- Paralysis of Phrenic Nerve: As the only nerve in the nervous system to provide motor (movement) function to your diaphragm, paralysis of the phrenic nerve can lead to paralysis of the diaphragm, which then results in a reduced breathing capability.
- Severe Tuberculosis with Resulting Lung Scar Tissue: Tuberculosis is a communicable disease caused by a bacterium that causes inflammation in the lungs, obstruction of the airways, and in severe cases, scarring of the lung tissue. The scarring makes the lungs stiffer and hinders efficient oxygen movement from inside the tiny air sacs in the lungs into the bloodstream.
- Severe Anemia: People with relatively severe anemia have symptoms of hyperventilation and a rapid heartbeat due to their bodies’ constant effort to restore oxygen levels to normal.
- Advanced COPD (Chronic Obstructive Pulmonary Disease): COPD causes the airways in your lungs to become inflamed, and the tissue where oxygen is exchanged is destroyed. When that happens, less oxygen gets into your body tissues, and it becomes harder to get rid of the waste gas carbon dioxide.
- Advanced Pregnancy: Breathing may be affected by the increase in progesterone levels and the enlargement of the uterus, resulting in pressure against the diaphragm.
References:
Biochemistry, R. L. P. D. I. (2021, November 23). Anemia: The disease that makes you feel like you’re running a never-ending marathon. https://www.biron.com/en/education-center/specialist-advice/anemia-breathing/
Cleveland Clinic (2022). Phrenic Nerve. https://my.clevelandclinic.org/health/body/22270-phrenicnerve#:~:text=Damage%20to%20a%20phrenic%20nerve%20can%20lead%20to%20a%20paralyzed,on%2001%2F09%2F2022.
Jovinally, J. (2018, November 7). COPD and High Altitude. Healthline. https://www.healthline.com/health/copd/high-altitude
Tortora, G. J., & Derrickson, B. (2014). Principles of Anatomy and Physiology (14th ed.). Wiley.
Why Do Some Pregnant Women Have Trouble Breathing? (for Parents) - Nemours KidsHealth. (n.d.). Retrieved from https://kidshealth.org/en/parents/breathing.html