Abdominal Support for the Diaphragm
There are basically four sets of muscle in the abdominal wall:–
- The Exterior Oblique Muscles
- The Interior Oblique Muscles
- Rectus Abdominis
- Transversus Abdominis
Oblique Muscles — Interior and Exterior
The Oblique Muscles (both Interior and Exterior) attach to the lowest rib and the costal arch at the top, and to the pelvis at the bottom. They run down obliquely. One set [note 1] slants down and to the left, the other down and to the right.
When only one set tightens, the torso twists in that direction.
When both tighten, the net effect is to pull and hold the ribs down and, also, to narrow the waist. It is worth pointing out that while, without using a corset, this is the only way to acquire a narrowed waist, you will pay a high price. There is a much better (healthier, happier, easier) way to achieve a flat belly.
Rectus Abdominis
Rectus Abdominis is a broad band of muscle running straight down from the costal arch to the pubic bone.
When this tightens, it also pulls and holds the ribs down. Tightened further, it bends the lumbar spine forwards and downwards. Together, these effects are responsible for the ‘concertina effect’. This is the cause of the rolls of flesh (‘spare tyre’) that typically appear around so many people’s hips — even for very slender people.
All Three Muscles Together
In extreme cases, these three muscles pull the rib cage so far down that it virtually rests on the crest of the pelvis (‘hip bone’). You lose a lot of height this way.
When you deliberately pull your belly in, they are the muscles you use — at what cost! Creating a flat belly this way plays havoc with your whole body. As you will see, the correct support for a flat belly is achieved quite differently.
Since these muscles pin your ribs down, they are unable to provide the support the diaphragm needs for its rib-lifting action. In fact, by resisting any movement of your ribs, they force you to tighten your chest in order to breathe at all.
Transversus Abdominis
Fortunately, you are better designed than you realise.
Your innermost layer of abdominal wall muscle, Transversus Abdominis, solves the problem. The part of Transversus Abdominis I’m talking about here is the lower part, down at the level of the pelvic bones (those bones we call our hips). It connects one ‘hip’ bone to the other. (NB: your hip bones are not the same as your hip joints).
Since this muscle is not attached to your ribs at all [note 2], it is able to provide the necessary support for the rib-lifting action of the diaphragm: it holds your guts in place (so keeping your belly very flat) without interfering with the movement of your ribs.
But, it can only do this when it is working
This brings us to another major difference from the other belly muscles: Transversus Abdominis is not under your voluntary control: you don’st choose to tighten it.
This is because it plays no part in moving your body about in space: it has a purely supportive rôle). It is stimulated to work only when it is carrying the weight of your chest sitting on your belly. [note 3]
Transversus Abdominis reacts to this outwards pressure by tightening just enough to hold everything in place — but only if the other abdominal muscles are not taking over. If the other abdominal muscles are habitually taking that strain, then it is never being stretched and so never stimulated to work.
The only way to persuade it to work, and the only way to achieve supported diaphragmatic breathing, is a combination of two factors:–
- Stop using the other abdominal wall muscles
- Allow your chest to be partly supported by your belly. (But that’s the subject of another article introducing you to your Demented Mechanic).
Habit is very persuasive and it takes a lot of personal experience of breathing in this way before you can let it happen. How do you get this personal experience? That’s where the Smiling Back Method comes in. Your next step in learning it is to find out about your Demented Mechanic.
One more thing
Not being used to working, Transversus Abdominis tends to be very weak. As a result, when you begin to use it, it will quickly get tired. As it strengthens up, however, all sense of strain disappears and using it becomes easy, automatic and effortless. This, I believe, is the essential difference between someone who ‘has guts’ and the crowd who haven’t — yet.
Previous part: Breathing
Notes
1. The left interior and right exterior oblique pull to the left: the right interior and left exterior pull to the right.
2. I am ignoring that part of Transversus Abdominis that fills the costal arch. It is not involved in the action I describe. Indeed it would tend to prevent it. Although classed as belonging to Transversus Abdominis, this part is best regarded as a separate muscle.
3. For a fuller discussion of this, see my concept of the Demented Mechanic which I first discussed in this article.
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