Several of my PT friends have referenced a physical therapist p who has studied breathing named Mary Massery. In her articles, she has referenced the idea of "intra-abdominal pressure"
See page 2
If I am understanding her correctly, she is basically saying that
- an unopened soda can is sealed and hard because of the pressure inside the canister
- the human trunk tries to support itself upright. In this sense it is rigid. Therefore, it too must be using an internal pressure to create the rigidify necessary for uprightness. This is what she calls "intra-abdominal pressure."
Given what is known about the mechanics of human breathing, do the pressures of the abdominal cavity actually behave this way? Does the abdominal cavity rigidity itself using some sort of pressure? If so, how does this pressure mechanism relate to the mechanisms used during respiration?
If I am understanding her model correctly, I am extremely skeptical. A soda can is really not similar at all physically to the abdominal cavity.