What do the names, internal and external intercostal muscles, mean?
Internal comes from the Latin word internus, which means within.
External means outside of.
The word intercostal comes from the Latin words inter, which means between, and costa, which means rib.
The internal intercostals then, are muscles between the ribs and located inside a structure, while the external intercostals are muscles between the ribs and located on the outside of a structure.
In the case of the intercostals, they are internal or external relative to one another.
Where do the internal and external intercostal muscles attach?
Origin
The internal intercostals originate and insert between adjacent ribs.
The external intercostals originate on the inferior border of the rib above.
Insertion
The external intercostals insert on the superior border of the rib below.
What actions do the internal and external intercostal muscles do?
The internal intercostals bring the ribs down during forced expiration.
The external intercostals elevate the ribs in inspiration.
Keep in mind that the abdominal muscles all have a role to play in forced exhalation.
Poses where we may be more aware of the internal and external intercostal muscles and breathing in yoga:
In postures like marichyasana C, we may notice that it is more difficult to breathe. The abdomen is compressed during the twist, so the ribs need to move more during the act of inhalation to accommodate that. The ribcage itself is also under more pressure from being stretched. This makes it harder for the ribs to separate and allow air in.
Learn All of Your Muscles
Join thousands of yogis when you sign up to our monthly newsletter
Check out our Online Courses and Workshops
- Enhance your practice
- Fine tune your teaching skills
- Go deeper into anatomy and yoga
Related Posts
How To Stretch The Quadriceps
David shares his favorite way to stretch the quadriceps. He describes how he uses a modified virasana to prepare for doing backbends.
How Much Are We Using Leg Muscles In Standing Yoga Postures?
David summarizes research which suggests that the leg muscles which stabilize the ankle are important in maintaining standing balance poses.
Coracobrachialis Muscle
David describes the coracobrachialis muscle. Find out where it attaches, what actions it does, and where we might be using it in yoga.