Kinesiologists have discovered that muscles work in chains which carry the energy flow from one part of the body to another according to very specific patterns. It has been established that the deep muscles of the back play a crucial role as the initial links in this sequence. That is how the state of the back can affect the state of the whole body. Bhujangasana, by working on the whole back, both the deep and superficial muscles, thus re-establishes and harmonizes energy flow in all the muscles, from top to toe.
The deep muscles of the back close to the spine are continuously at work during the waking state. Because they are short and strong, they are much more difficult to relax than the longer, more superficial muscles. Bhujangasana is the ideal method of contracting them, so that when the posture is released, they are automatically relaxed and rejuvenated.
The main deep muscles affected by bhujangasana are the transverspinatis, supported by the inter-transversari and the interspinales. Until recently, some of these muscles were thought to be secondary but nowadays they are recognized as having two main functions. Firstly, they give the initial impulse which causes the other muscles of the back to straighten. They are in fact the ignition devices of the muscle chains, the expression of the fire element in the spine.
Secondly, these deep muscles are considered to be the sentinels of the spine. They protect its precious material, even at the cost of stiffness and spasms which can last a lifetime. The proper practice of bhujangasana, adapted to one's individual condition, is a means of relieving or preventing the spasms from setting in and of allowing a free flow of energy along the spine.
According to the theory of muscle chains developed by G. Struyf, a kinesiologist in Belgium, these deep muscles of the back are part of an energy pattern which includes the respiratory muscles. This particular muscular chain is characterized by rhythm- the rhythm expressed by the breath function. This is why it is of utmost importance that none of the muscles of this chain go into spasm. Otherwise, the whole rhythm of life in the individual microcosm is disturbed.
Energy from the deep muscles is conveyed to the para-vertebral muscles on either side of the spine which keep the spine erect and give a structure to the back. As well, they carry energy impulses upwards, all the way to the forehead and eye orbits, via the aponeurosis, a flat, thin tendon which covers the skull. Therefore, by balancing the energy in the back, bhujangasana can also relieve tension and energy disturbance in the head and eyes.
Other muscles carry tension or relaxation from the back to the arms and legs. For example, in the classical pose of bhujangasana, when the legs are kept together, the buttocks are alternately contracted and relaxed. This influences the gluteus maximus muscles attached to the sacrum, which in turn affects the muscles of the legs. Furthermore, according to the kinesiologists, the sacrosciatic ligament where the gluteus maximus takes its origin is an important linkage for the flow of energy to communicate between the muscles in the front of the body and those in the back. Bhujangasana, of course, also affects the ventral muscles directly by the stretch applied in the extension of the trunk. Therefore, through only one posture, we are able to sweep the whole body of excess tension and remove energy blocks.
Bhujangasana also rejuvenates the blood circulation. This is why the back often becomes red after the practice. After the contraction of the neck muscles, the brain receives a fresh supply of blood from the internal carotid and vertebral arteries. The nervous roots emanating from the spine are irrigated. Bhujangasana also massages the abdominal muscles and solar plexus, thereby improving intestinal function and digestion, and helping to unlock the anxiety which is so frequently stored in this region.
The kidneys and adrenal glands are also influenced through direct pressure and the renewal of the blood circulation. Dr. K.N. Udupa of Banaras Hindu University included bhujangasana in a yoga program for cardiac patients, and after three months of practice a decrease in adrenalin and noradrenalin levels in the urine to within normal limits was noted.
Bhujangasana stimulates and strengthens the nervous system and through it, the vital functions. It influences the sympathetic nerves that arise in the dorsal and upper lumbar regions, thus increasing dynamism and harmonizing genital functions. At the lumbar and cervical levels, the part of the peripheral nervous system related to the arms and-legs is influenced.
Just as the serpent seeks release from the influence of gravity to find its balance between air and earth, many vital functions can also find a better balance through the practice of bhujangasana. The upper part of the body is forced to expand and break away from the stiffness and resistance that envelop the spine. It is like a calling from the higher part of ourselves to be delivered from the restrictions of the earth element.
In the classical pose of bhujangasana, concentration is focused first on vishuddhi chakra, and then on manipura. This occurs when the whole spine has been made supple and strong, and the entire process of the sadhana has been completed. However, during the evolution of the posture, while flexibility is being developed in each part of the spine, all seven chakras are affected.
As we raise the head backwards, concentration on the eyebrow centre often takes place naturally. This influences ajna chakra and awakens intuition - the higher knowledge of the serpent.
Vishuddhi chakra, in the throat, is the centre of purification where all dualities and contradictions are resolved. This aspect is symbolized by the story of Shiva, whose throat was burned by the poison brought up during the churning of the ocean. It is at vishuddhi that the nectar and poison are separated, enabling the yogi to exist for long periods without food or water. If this centre can be controlled, the process of aging can be reversed and the longevity of the serpent gained.
Bhujangasana directly affects anahata chakra as well, because of its central position in the dorsal region of the back. The posture releases the tension and fear which so frequently build up in this area, blocking the expression of the inherent human qualities of compassion and warmth.
The attributes of manipura chakra are symbolized by the snake's capacity to swallow and digest huge quantities of food, in all shapes and sizes. In bhujangasana, the abdominal region remains in firm contact with the earth and provides the support and strength for the whole posture. This stimulates manipura chakra, and promotes physical and digestive fire.
Bhujangasana acts like a pressure cooker, forcing energy down the spine with ever increasing pressure. As the posture develops, the pressure reaches swadhisthana, storehouse of the samskaras, the deep archetypal patterns of the human mind. At every level, vertebra after vertebra, chakra after chakra, the pressure mounts, until finally the contraction gathers at the very root of unfoldment of life- mooladhara chakra. All the pressure now is locked in mooladhara. Then, when the pose is released and the spine relaxed, the energy is launched back up the spine to awaken the higher centres. This is the realization of the tradition stated in the Gheranda Samhita: "By the practice of bhujangasana, kundalini is awakened."