Some thoughts from personal experience on this topic. This entry is mainly based on self-analysis, on the basis of which I draw some general conclusions; I freely admit the methodological flaw in this way of reasoning (and even more so since I am not a “pure” example of this body type*), but those who are interested in a more systematic account will anyway refer to the literature on the subject. So:
By virtue of repeated violence and threats of violence during early childhood, the masochistic body type (“Maso”) develops two sets of marked body patterns.
Firstly, spasticity of the following muscles or muscle groups: (i) buttocks and thighs (gluteus medius and minimus, pectinius, quadriceps, rectus femoris, and the hip adductors); (ii) the deep pelvic and perineal muscles (the pelvic floor, which consists of three muscles, and the perineal pouch, see here for photo) involved in defecation and urination as well as in maintaining posture and (iii) the transversus and rectus abdominis muscles.
The original purpose of tensing these muscles was to protect the genitals from damage. The need to protect the genitals also has a symbolic interpretation and charge, insofar as it represents an attempt also to defend the ego from assault. The spasticity of these muscles is naturally paired with a lack of tonus in the muscles which move the hip and pelvis upwards and outwards.
Associated with this, a pattern of breathing is developed in response to pain and assault whereby oxygenation of the pelvic region is reduced, and thereby also its sensitivity to pain. This appears to involve primarily the transversus abdominis muscle, which is the deepest of the abdominal muscles and inserts into the linea alba (the line which runs from the solar plexus downwards). Spasticity of this muscle effectively shuts off energy flow along the front of the body, separating the pelvic region from the abdomen. It also limits the depth of abdominal breathing.
In addition to this, the Maso develops constrictions in the jaw and throat, running as far down as the solar plexus and also involving the pectoral muscles. These constrictions aim at inhibiting the vocal expression of anger and pain. The effect of constrictions in this segment is also to draw the shoulders forward and to compress the sternum from the manubrium (upper part of the sternum) which is compressed by the clavicles until the xiphoid process (region of the solar plexus).
In combination, these two groups of muscular spasticities arch the spine in the form of a C, a posture which expresses and communicates resignation and defeat.
Such spasticities develop in early childhood and inevitably have a permanent developmental impact at the skeletal level. The anatomy in particular of the pelvis/hip area is affected by the imbalance between muscle pairs which results from permanent tension in the adductor muscles.
The Maso’s energy economy is characterized by a high level of primary energy in the genital region but a limited ability to circulate and use this energy, requiring discharge at low thresholds, or otherwise manifesting as anxiety. Essentially, the Maso is unable to tolerate a high level of energy is his body, because of the fact that this energy overcharges the genitals. Compulsive masturbation is a way to avoid anxiety. Anxiety manifests itself because the discharge of energy has been blocked. As anxiety increases, discharge scripts are cathected. These scripts are typically sexual in character and develop into more or less developed forms of obsessive-compulsive behaviour. Such scripts may be actually enacted, or merely direct the expression of sexual desire. The masochistic character also has a tendency to overuse and possible abuse of alcohol. In my case there is also a tendency to compulsive eating and obesity, which is a common, but I am not sure whether general, characteristic of the body type.
Clearly, the therapeutic challenge is to loosen these two sets of primary rigidities and to deepen the breathing so that the pelvic area is better oxygenated.
*) As regards physical body armoring, however, I think this type predominates, both based on self-observation and on theoretical grounds which I omit.