The primary muscle of respiration is the diaphragm.
The Diaphragm: The Major Muscle of Breathing
The diaphragm, a large, dome-shaped muscle situated beneath the lungs, is the most important muscle for breathing. It rhythmically and mostly involuntarily contracts and relaxes, enabling inhalation and exhalation. During inhalation, the diaphragm contracts, flattening and enlarging the chest cavity, allowing air to fill the lungs. MedlinePlus Medical Encyclopedia Image, Cleveland Clinic
Other Respiratory Muscles
While the diaphragm is the principal muscle, several other muscles contribute to the respiratory process:
- External Intercostals: These muscles between the ribs assist in inhalation by expanding the chest cavity. Physiopedia
- Rib Cage Muscles: Along with the external intercostals, other rib cage muscles play a role in both inhalation and exhalation. PMC
- Abdominal Muscles: These muscles aid in exhalation by compressing the abdomen and forcing air out of the lungs. PMC
- Accessory Muscles: In situations requiring increased respiratory effort (e.g., exercise or illness), accessory muscles like the sternocleidomastoid and scalenes may be recruited to assist with breathing.
Understanding the Respiratory Process
The process of breathing is a complex interplay of muscle actions, nerve signals, and lung elasticity. While the diaphragm plays the most significant role, the coordinated action of multiple muscles ensures efficient gas exchange. Wikipedia, Merck Manual
