The following series of articles, an in-depth look at Yoga has been compiled by Merel Martens founder of Parimukti Yoga and produced and packaged by Avdhoot Limaye for Parimukti.com. In Part 6 we will do a Introduction to pranayama and in part 7 we will examine the Deeper nuances of Pranayama practice.
“Pranayama is the link between the mental and physical disciplines.While the action is physical, the effect is to make the mind calm, lucid and steady” Swami Vishnu-Devananda
Pranayama is often split into ‘prana’ and ‘yama’ translating it into ‘breath control’. However, it is actually comprised of the words ‘prana’ and ‘ayama’, which means ‘pranic capacity or length’. Pranayama is more than just controlling the breath. Its primary purpose is to awaken prana, to maintain a healthy body and mind, and to prepare ourselves so that we can become aware of the more subtle levels of our existence. Pranayama calms and strengthens the mind and creates a feeling of internal space.
Puraka and Rechaka
Puraka means inhalation and rechaka means exhalation. Inhalation is the active process of respiration, and requires muscular effort to draw air into the lungs. Normal exhalation is passive, not requiring muscular effort. Rather the diaphragm and ribcage recoil back into their original place. In Pranayama rechaka is a slow, guided and controlled process. Generally, it is either the same length as, or twice the time of pooraka. The main advantage of conscious echalation is that it develops consicious control over the relaxation response.
Slowing the inhalation and exhalation in Pranayama, as in Nadi Shodhana and Ujjay, has many advantages in terms of our health. More oxygen is available, for example, with blood gases and digestion improves. It aids in slowing the heart rate and lowering blood pressure, as has been proven many times in mediation research. One becomes less ‘hyped up’. This process aids rest and recuperation of energy.
In Pranayama we occasionally speed up inhalation and exhalation, as in Bhastrika and Kapalbhati Pranayam. These techniques exercise the lungs and abdomen, and stimulate the nervous system to balance and strengthen itself. For more advanced practices of pranayama we involve Kumbhaka, or breath retention.
Kumbhaka means breath retention, either after inhalation (antar kumbhaka) or after exhalation (bahir kumbhaka). According to Patanjali, pranayama is actually only retention:
Kumbhaka is not designed to increase the absorption of oxygen into the bloodstream. The processes of diffusion of gases between the lungs and the bloodstream depend mostly on the surface area available for diffusion, the condition of the alveolar membrane, and the partial pressures of gases on either side of the membrane. It is not so dependent upon the time factor. Once the pressure of the gases on either side of the membranes is equalized, diffusion stops. Hence, withholding the breath for a longer time does not afford any real advantage as far as the absorption of oxygen is concerned. Rather, during Kumbhaka oxygen levels fall in the body and carbon dioxide levels increase.
The main effect of kumbhaka is to train the nervous system to tolerate higher levels of carbon dioxide in the body, before signals from the primitive brain stem force us to take another breath. This may seem contradictionary, if pranayama is considered as a more efficient breathing method only. However, the longer the breath is held, the great the gap between the nervous impulses and their responses in the brain. When breath retention is held for a prolonged period, mental agitation is curtailed.
Control of breath
As we stated above, Pranayama is more than control of breath. However controlling the breath opens the door to controlling the quantity and direction of prana.
Our body needs oxygen for all the metabolic process in our body. The process of metabolism is a complex cellular activity in which substances are manufactured and broken down by the cells of the body. In this process, energy is stored and released for all its complex functions. Oxygen is required for many chemical reactions in which carbon dioxide and water are formed as waste products. Respiration is the action of bringing oxygen from the atmosphere to the lungs and the bloodstream, and then to all the cells of the body.
There are two levels of respiration. The first one is external respiration: Air is drawn into the lungs and exchange of oxygen and carbon dioxide takes place in the alveoli, the small dilated air-sacs which are lined with a network of capillaries. The second is internal respiration: this happens in the cell. Oxygen moves from the bloodstream into the cell and carbon dioxide moves from the cell into the bloodstream. Most of the times our breath happens unconsciously: nervous control of respiration is mainly determined by levels of carbon dioxide (a waste product of metabolism) in the blood.
During periods of increased metabolic activity, such as during physical exertion, higher blood levels of carbon dioxide cause the medulla oblongata to send signals to raise the frequency and depth of breathing. The medulla lies at the base of the brain (primitive brain) from where impulses are send via the spinal nerves to the diaphragm and intercostal muscles.
Although breathing normally functions unconsciously, we also have the ability to take conscious control of it. In this the respiratory system is unique, other unconscious processes such as the heartbeat, body temperature and metabolic activity, cannot be controlled by the average person. Conscious control of the breath comes by engaging the more evolved areas of the brain in the cerebral cortex, by-passing the respiratory center in the brain stem.