Section 2-3. “Hazo” is a linchpin for muscles in the whole body

Among lots of joints in our body, only sacroiliac joint and mandibular joint are bilaterally located around the midline (Figure 47). When we take a standing posture against gravity and atmospheric pressure, these two joints play a definitive role as the linchpin for all the muscles including anti-gravity muscles because these joints are located symmetrically around the midline. Particularly, “mandibular joint” is closely correlated with a group of muscles in the head and neck which support the head, besides being capable to move flexibly unlike the sacroiliac joint. Accordingly, whenever we bend forward or backward, it is conceivable that these joints exhibit important functions as “balancer” for the whole muscles in the body. It is obvious from the so far reported study results on electromyograms that the chewing muscles and muscles located in the head and neck areas with general muscles in the body coordinate each other as one system. In more details, it was evidenced that tension of chewing muscles generates simultaneous involuntary discharge in various skeletal muscles in the body to always induce increased muscular tonus. It was also documented that electric discharge occurred in the remote muscles from teeth, such as extensor muscle of the forearm and gastrocnemium muscles in legs.
In relation to the fact that systemic muscles are involved in “Hazo” mechanisms, Dr. Noguchi Michizo mentioned in his book entitled with “Noguchi gymnastic exercises are effective for physical conditions” (Hakuju Sha) that “Our body is a living wineskin”, namely “In living human bodies, body fluids are packed in a living skin bag in which bones and visceral organs are floating.” It seems that muscles have hardness to support the skin and temperature maintenance effects. In talking about the skin bag, there should be an inlet and an outlet. Yes, there are a mouth and an anus. The skin bag is tightly closed with these inlets. In the book written by Tenpu Nakamura, there is an expression “You must constrict your anus with attention on muscles”.
I wish to review the concept comparing to the wineskin by referring to the fundamental structure of humans. The basic structure of humans comprises the vertebral column traversing the trunk longitudinally, “Central nerves” lying dorsal to the column and “Digestive tracts” located ventral to the column starting from mouth to anus. This structure is commonly observed in the fish ancestors who appeared on the earth about 570 thousand years ago, and their descendant vertebrates. In other words, human bodies resemble “macaroni” in that digestive tracts penetrate the human bodies. Surrounding these digestive tracts, “visceral organs” gather together and “body wall” covers them. If we compare human bodies to the wineskin, the body is called as a double-structure, with the internal wineskin called as the digestive tracts having mouth and anus at both ends. The muscles under this wineskin are connected mutually, indicating a system. Incidentally, under the outer wineskin there are lots of skeletal muscles while under the internal wineskin, there are many smooth muscles related to visceral organs.
As the linchpin of the muscle systems comprising the inlets of this wineskin, there are chewing muscles involved in moving mouth and chewing foods, suprahyoid muscles and infrahyoid muscles and other muscle groups connecting cranial bone, neck and breast. Chewing muscles consist of temporal muscle, mesenteric muscle, internal pterygoid muscle, and external pterygoid muscle. Suprahyoid muscles located above the hyoid bone consist of mylohyoid muscle, digastric muscle, stylohyoid muscle and geniohyoid while infrahyoid muscles, located below the hyoid bone comprise thyrohyoid muscle, sternomastoid muscle, sternohyoid muscle and omohyoid muscle. Contraction of suprahyoid muscles and infrahyoid muscles is associated with lowering of lower jaw resulting in causing the opening movement. At this occasion, chewing muscles as the antagonizing muscle are relaxed. Subsequent contraction of chewing muscles induces opening movement and chewing movements. The muscles connecting other cranial bones with cervical and thoracic parts consist of platysma, sternocleidomastoid muscle, rectus capitis posterior major muscle, rectus capitis posterior minor muscle, obliquus capitis superior muscle and obliquus capitis inferior muscle. The ligaments of these muscles work as the string are considered to loose or close the wineskin. In the similar manners as the human body is regarded as one micro-cosmos, muscle systems are not sufficient to complete the systemic systems of our body but the muscle systems should be coordinated with visceral organs and other systems including meridian (the concept derived from the Oriental medicine).