Exploring the diaphragm muscle
The diaphragm muscle is unlike any other. In essence, it attaches onto itself. Typically, a muscle attaches from one bone to another bone. It then usually moves the less stable of those two bones (depending on circumstance) toward the more stable bone when it contracts, but not the diaphragm. Its contraction creates a large pattern of movement in the rib cage, abdominals, and of course inflation of the lungs.
What does the name diaphragm muscle mean?
The word diaphragm comes from several Greek words:
- dia, which means across
- phragmos, which means a fence
- phrassein, which means to enclose
You could get the idea, then, that the diaphragm encloses something. It does, in the sense that it divides the abdominal cavity from the thoracic cavity.
Where does the diaphragm muscle attach?
The diaphragm separates the thoracic cavity from the abdominal cavity. It has three openings: the esophagus, the inferior vena cava and the aorta.
It originates on the L1-L5 vertebrae, the lower 6 costal cartilages, and the xiphoid process.
It inserts onto the central tendon of the diaphragm. In other words, it inserts on itself.
What actions does the diaphragm muscle do?
The diaphragm does most of the work during breathing. As it contracts it flattens, pulls on the lungs, and creates a negative pressure to allow more room for air to fill the lungs.
Poses where we may be more aware of the diaphragm muscle and breathing in yoga
In postures such as bound twists like marichyasana C, we notice that it is more difficult to breathe. This is for two reasons: 1) the abdomen is compressed during the twist which means it can’t push out as easily or at all; this means that the ribs need to move more during the act of inhalation, 2) the rib cage itself is under more pressure, it is loaded with tension from being stretched in the twist; this makes it harder for the ribs to separate and allow air in.
In backbending postures such as urdhva dhanurasana, the abdomen is taut from being lengthened and the ribs are already stretched apart from the positioning of the spine. This makes it harder to inhale.