The diaphragm is a significant muscle located beneath your ribs, playing a central role in breathing and other bodily processes. It forms a partition within your torso, acting as a dynamic divider.
The Diaphragm: Your Key Breathing Muscle
The diaphragm is a sheet of muscle and fibrous tissue at the base of your chest, beneath your lungs and heart. It serves as a physical barrier, separating the thoracic cavity (housing the heart and lungs) from the abdominal cavity below. This muscle has a distinctive dome shape, curving upwards into the chest when relaxed.
As a skeletal muscle, the diaphragm is subject to both involuntary and voluntary control. It continuously works without conscious effort to maintain breathing, but individuals can also consciously control its actions, such as holding their breath. The diaphragm attaches to various skeletal structures around the lower rib cage, including the sternum, ribs, and lumbar vertebrae. Muscle fibers from these attachments converge into a central tendon, forming the peak of its dome shape.
How the Diaphragm Works
The diaphragm’s primary function is respiration, drawing air into and expelling it from the lungs. During inhalation, the diaphragm contracts and flattens, moving downwards. This increases the thoracic cavity’s volume, creating a pressure difference that causes air to rush into the lungs.
When exhaling, the diaphragm relaxes and returns to its dome shape, moving upwards. This reduces the chest cavity’s volume, pushing air out of the lungs. Beyond breathing, the diaphragm also assists in other bodily functions by increasing intra-abdominal pressure. These roles include coughing, sneezing, urination, and defecation.
Understanding Diaphragm Sensations
People often experience various diaphragm sensations, most of which are temporary and harmless. Hiccups are common involuntary spasms of the diaphragm. These spasms cause a sudden intake of air, followed by the rapid closing of the vocal cords, producing the characteristic “hic” sound. Hiccups can be triggered by factors like eating too quickly, consuming carbon beverages, or emotional excitement.
Another familiar sensation is a “side stitch,” often experienced during physical activity like running. This sharp pain, felt under the lower edge of the ribcage, is a cramp or spasm of the diaphragm. Its exact cause is not fully understood, but it may relate to irritation or insufficient blood flow during exercise. Diaphragm fatigue can also occur after intense physical exertion, leading to breathlessness or discomfort. These sensations are usually minor and resolve on their own.