EUPNEA, A.K.A. QUIET BREATHING
It is a mode of breathing that occurs at rest and does not require the cognitive thought of the individual. During eupnea, also referred to as quiet breathing, the diaphragm and external intercostals must contract.
HYPERPNEA, A.K.A FORCED BREATHING
It is a mode of breathing that occurs during exercise or actions that require the active manipulation of breathing, such as singing. During hyperpnea, also known as forced breathing, inspiration and expiration both occur due to muscle contractions.
In addition to the contraction of the diaphragm and intercostal muscles, other accessory muscles must also contract: During forced inspiration, muscles of the neck, including the scalenes, contract and lift the thoracic wall, increasing lung volume. During forced expiration, accessory muscles of the abdomen, including the obliques, contract, forcing abdominal organs upward against the diaphragm. This helps to push the diaphragm further into the thorax, pushing more air out. In addition, accessory muscles (primarily the internal intercostals) help to compress the rib cage, which also reduces the volume of the thoracic cavity.
DIAPHRAGMATIC, A.K.A. DEEP BREATHING
It is a mode of breathing that requires the diaphragm to contract. As the diaphragm relaxes, air passively leaves the lungs. This type of breathing is also known as deep breathing. It is also known as natural breathing as when babies are born, they display that type of breathing (you can see their belly go up and down).
COSTAL BREATHING, A.K.A. SHALLOW BREATHING
It is a mode of breathing that requires contraction of the intercostal muscles. As the intercostal muscles relax, air passively leaves the lungs. This type of breathing is also known as shallow breathing and it is the breathing style of anxiety.