Many muscles in the body affect the breathing process from the nose all the way down to the bottom of the abdomen. The respiration process relies on the upper respiratory system and the lower respiratory system. The upper respiratory system consists of smaller muscles in the neck and head that pull air into the body. The lower respiratory system are muscles are located around and below the lungs that help you to exhale.
Upper Respiratory System
The upper respiratory system consists of several muscles in the head and neck responsible for the initial pull of breath into the body as well as the final stages of exhalation. The nasal cavity, or nose, contains muscles that pull air into the pharynx. The oral cavity is also responsible for pulling air inward. The pharynx, or throat collects incoming air and passes it downward to the trachea, or windpipe. From the pharynx, the trachea pulls air down into the lungs.
The Diaphragm
The diaphragm is technically part of the lower respiratory system, however, it deserves special attention because it is the largest and most instrumental muscle in the breathing process. The location of the diaphragm is just under the lungs, separating them from organs below. Proper breathing starts from the diaphragm which moves down and flattens, flaring the ribs outward. The lungs then expand, drawing air in as the muscles of the upper respiratory system assist the inhalation process. As the diaphragm relaxes, the lungs contract and expel air in the process known as exhalation. Similar to a balloon, the lungs require pressure to fill up but will expel air once released, with no external energy.
Lower Respiratory System
The lower respiratory system consists of the intercostal muscles, the abdominal muscles and the accessory muscles. The intercostal muscles are located between the ribs and allow you to take very deep breaths and cough. The abdominal muscles are the most essential muscles for a deep cough. Also, the abdominal muscles allow you to force air out through a powerful blow when they are contracted. The accessory muscles are located in the neck but are part of the lower respiratory system because they act to elevate the rib cage, assisting in deep respiration.
