Asanas greatly influence the functioning of the endocrine system. We know the important role the endocrine glands play during stress adaptation, by secreting the stress hormones. There is such an intricate relationship between the glands that one malfunctioning gland can cause the disruption of the whole system.
Asanas bring about harmony in the functioning of the various other bodily systems, which are closely interwoven, such as the circulatory, nervous, respiratory, and digestive systems. Any disruption in the proper working relationship between these systems results in loss of health and body efficiency. Here again, all these systems play an active role during the body's adaptation to stress.
The subtle influence asanas bring about in the body is in the pranamaya kosha or the energy sheath. Pranamaya kosha is pervaded by what is known as bio-plasma or bioluminescence or prana, which the Kirlians had photographed for the first time. This energy travels in and around the body in specific pathways or the nadis, creating the aura around the bodies. These nadis or pathways become easily blocked, and prana gets congested in certain areas. When this happens, it leads to physical and mental disorders. Prana is also intimately connected to the mind. The free flow of prana brought about by asanas, leads to mental equilibrium and calmness.
Rapid and irregular breathing signifies tension in the mind and body, whereas slow, deep and rhythmical breathing indicates both calmness in the mind and good health. The practice of asana brings about mental and emotional equanimity, by slowing down the breathing, and by deepening the inhalation and exhalation.
Finally, the practice of asana with body and breath awareness, keeps the mind off tension and worry, at least during the practice. However, the temporary relaxation achieved during the practice, gradually builds up to bring permanent changes in one's mental and emotional makeup. As our mental attitude is reflected in our body, in the same way physical poise achieved during the practice of asanas has a corresponding effect on the mind.
The pawanmuktasana practices are taught preliminary to the practice of asanas, and are divided into:
'Pawan' means 'wind', 'mukta' means 'release' and the pawanmuktasana group of exercises releases excess of wind and acidity from the body.
Though in practice, these seem very simple, they exercise subtle effects on the different joints and organs of the body. That's why these are known as sukshma vyayama or subtle exercise in Sanskrit.
Along with the excess wind and acidity, the practice also removes or releases muscular tension from all over the body, from the head to the toes, and balances the pranas in the body. This in turn helps to keep the body balanced and stress-free throughout the day.
We have already seen how all the asanas directly or indirectly influence and stimulate the endocrine system, which plays a key role during the body's adaptation to stress. However, no single practice influences the body-mind complex to the same extent as surya namaskara does. It can be considered as stress management in a capsule!
The practice of surya namaskara has three major aspects: form, energy and rhythm. The twelve postures in surya namaskara create the physical matrix around which the form of the practice is woven. These postures generate prana, the subtle energy which activates the psychic body. Their performance in a steady, rhythmic sequence reflects the rhythms of the universe, and the biorhythms of our own body. The rhythmic superimposition of this form and energy, on our present body-mind complex is the transforming force which generates the nucleus of a fuller and more active life and a greater appreciation of the richness of the world we live in.
In the subtle body of man, there are seven major psychic centres called chakras. They have their physical representation in the various nerve plexuses and the endocrine glands. The activation of these psychic centres through surya namaskara proceeds mainly through the development of internal awareness, concentration and visualisation.
Each of the twelve poses in surya namaskara has its own mantra which is mentally repeated for greater benefit. The actual physical stimulation from each pose enhances prana shakti, allowing us to better focus and concentrate our mental and physical energies at the chakra location. It is this dual aspect of taking our mental awareness to a highly charged physical structure which leads to a fusion of mind and body, ida and pingala.
The forward and backward physical movements in surya namaskara alone are enough to stimulate our metabolic rate to release energy. When these are combined with chakra stimulation, then the effects get enhanced.
The spinal cord, the link between the brain and the body is the conduit for all our energies. Within it are the ida and pingala nadis, so its health is of paramount importance. Surya namaskara, being an active and dynamic series, exerts its major influence on pingala nadi, especially when it is practised quickly. However, when practised slowly and completely with chakra awareness and mantra repetition, surya namaskara stimulates both ida and pingala almost equally. In the slower version, the technique transforms itself from a series of asanas to a series of mudras, leading to a more balanced development As we analyse each of the poses in surya namaskara, we understand the tremendous therapeutic influence that is brought on stress, through a combination of asanas, pranayama, chakra awareness and mantra repetition.
According to the ancient science of ayurveda, all the body functions are controlled by three humors: kapha (mucus or phelgm), vata (gas or wind) and pitta (acid or bile). The first step to balancing the pranas is regulation of the humors. When we cleanse the body internally from time to time, we remove the excesses of these three metabolic products, thereby regulating their formation and balancing the proportion of each. However, in order to cleanse the body of these excesses, we have also to cleanse the nadis or the energy pathways.
Hatha yoga traditionally prescribes the shatkarmas or six ways of purifying the body; neti, dhauti, basti, nauli, kapalbhati and trataka. These are not mutually exclusive, but are practised in different combinations to suit the specific nature of disorder and individual need. The very fact that so many methods and techniques of cleansing the body have been developed, and are being practised, shows the great importance which hatha yoga attaches to the health of the body.
Neti is a process of cleansing the nasal passages of all impurities, including engrained dry mucus which can remain inside. On another level, the practice of neti has a subtle influence on the various nerves which end in the nasal passages, such as the olfactory bulb and other adjacent nerves, which enervate the eyes, ears, nose and throat. This has a soothing influence on the brain, and can help to relieve such stress-related ailments as migraine, asthma, depression, tension headaches, insomnia and tiredness.
We know how alternate nostril breathing has a balancing influence on the two hemispheres of the brain. The practice of neti has a similar effect, and induces harmony and balance throughout the central nervous system, as well as the systems that govern the respiratory, circulatory and excretory functions. Neti also enhances the efficiency of the frontal lobes of the cerebrum, which is responsible for the higher mental faculties.
Dhauti consists of several stomach washing techniques. Kunjal is the technique of cleansing the stomach by voluntary vomiting after drinking six glasses of warm salt water. Kunjal helps to remove acidity, gas and excess mucus from the stomach, and tones and stimulates all the abdominal organs. It removes the symptoms of stress and tension by stimulating the vagus nerve which triggers the parasympathetic nervous system and thereby, the relaxation response.
On the psychic level, kunjal strengthens the solar plexus or manipura chakra. The vomiting reflex pulls the prana up from the mooladhara chakra to the throat, and stimulates vishuddhi chakra. The upward movement of prana activates all the chakras within the vertebral column, and the surrounding nadis. Nerve impulses rush up from the base of the spine to the medulla oblongata and ajna chakra.
Shankhaprakshalana is another widely used dhauti technique. Shank means 'conch' and prakshalana means 'to wash completely'. This practice helps to wash the conch shaped intestines. It is a systematic and gentle method of completely washing the entire alimentary canal from the mouth to the anus. How shankhaprakshalana helps to remove stress? Toxic build-up in the digestive system produces a digestive stress, eventually resulting in different types of digestive disorders. These toxins are also circulated to other parts of the body where they again become a cause of stress and imbalance. By cleaning the entire digestive tract, we eliminate one of the major causes of physical stress, imbalance and disease, and thereby promote the health of the entire body.
Kapalbhati removes impurities from the frontal region of the brain and makes the mind calm. The most outstanding benefit of this practice is the reversal of nerve reflexes. Normal breathing is characterised by active contraction of only the inspiratory muscles, such as the diaphragm and the external intercostals; expiration occurs passively on the cessation of this contraction of the internal intercostal. Kapalbhati reverses this process: exhalation is active and inhalation is passive. This induces a reversal in the flow of the nerve impulses to and from the brain, bringing about stimulation and awakening of the brain centres.
Trataka. We have seen earlier (in Brain, the Controller), how mental concentration has a strong influence on the pineal gland and the sympathetic nervous system (since the eye is directly connected to the pineal gland via the sympathetic nervous system), and the hypothalmus and, through the hypothalamus, the wake fullness in an individual. When these centres are stimulated during the practice of trataka, the mind becomes steady and still, while all disturbing or stressful thoughts are blocked.