We have already discussed in details the effects of the snake breathing, or the Ujjayi, in our article “Some Effects of Ujjayi, or Relaxation after Victory”. Another important effect of the practice that results from systematic application of this pranayama is the training of muscles of the pharynx, tongue and soft palate that the medicine of today refers to respiratory muscles and that suffer from sleep apnea syndrome.
In order to clarify the perspective of Ujjayi-pranayama in yoga-therapy of people suffering from snoring and sleep apnea syndrome I suggest that we should turn our attention to the modern medicine concept of the breathing act, and in particular on physiological mechanisms of the afore-said muscles’ involvement within the breathing pattern.
Let us start from brief background.
The “classical” mechanism of respiratory activity that has been used in medicine for the recent century is the following: the lack of oxygen or excess of carbon dioxide in one’s organism stimulate the respiratory center that sends a respective command to inspiratory muscles (the diaphragm, intercostal muscles, small and large pectoral muscles together with abdominal muscles, the muscles of back and neck). The work of muscles increases the volume of the chest, the lungs expand and the air comes to alveoli as per the gradient of pressure. The active inhale is followed by passive exhale.
What concepts of inhalation and exhalation act exist today?
Recent researches have shown that the provision required for active involvement of inhalation muscles is the primary «initiation» of muscles of pharynx, tongue and soft palate. Normally their tone rises 100-200ms prior to inspiratory impulse on a diaphragm due to an impulse that comes from the neurons of the Betzinger complex in the cerebral trunk (these neurons manage the person’s respiratory rhythm) (Feldman J.L., Mitchell G.S.,2003; Reckling J.S., Feldman J.L.,1998).
The raising tone of the listed muscles causes opening of true glottis and relaxation of bronchial muscles, thus providing the path for the flow of air. And it is only then that the main respiratory muscles shall get involved, pulling the air that passes through the larynx into the alveoli of the lungs.
What is the way the malfunction of the upper respiratory tract muscles declares itself?
If for any reason the nasal, laryngeal or oropharyngeal muscles have not been involved in the act of breathing, the deflation of upper respiratory tract shall occur. The complete deflation shall cause apnea (from Old Greek. Ἄπνοια, simply, «calm», absence of respiratory activity, cessation of respiratory movements) and the incomplete one shall lead to hypopnea. Such respiratory standstills when occur chronically lead to changes in arterial blood gas and gas of body tissues — the hypoxia (oxygen deficiency), hypercapnia (excess of carbon dioxide) and respiratory acidosis (decrease of pH). The reason is simple — the human body is not properly oxygenated.
In most cases such mechanism is activated during sleep, since in terms of one’s sleep the amount of ventilation is reduced, the air flow slows down, the airway resistance is increased and neuronal activity of Betzinger center becomes more vulnerable (Orem J., 1986, Sielber A.P.). That is why the disease was called the “sleep apnea syndrome” (SAS), or the obstructive apnea-hypopnea of the sleep (OAHS).
In terms of different people sleeping process such periods shall occur with different frequency. In case the periods of respiratory standstills occur more than 10 times per hour, and each of them lasts more than 10 seconds, we can say that the disease state of sleep apnea syndrome has already been initiated at a person’s organism. If respiratory standstills occur rarely, we speak about the pre-disease state when the body is not functioning properly but still has enough reserves for recovery.
Why were such modifications referred to disease?
Because due to such disorder of respiratory pattern all organ systems become affected. The hypoxia and hypercapnia that are preserved during the daytime cause development of daytime sleepiness and increased fatigue, they lead to metabolic disorder and impaired blood composition. In some time the lungs shall lose their ability of proper functioning, and this shall be followed by pulmonary heart or paroxysmal dyspnea, respiratory failure and chronic renal failure, rise of intracranial pressure etc.
They single out several forms of such disease, one of them being nocturnal snoring with episodes of sleep apnea. In fact, this snoring is the sound that occurs when air passes through stenosed nasopharynx, caused by vibration in the air flow of compliant structures of the pharynx (tongue, soft palate, etc.). The main reason that causes vibration of the said formations is impairment of muscle tone of the pharynx and soft palate, structural anomalies and functional abnormalities of the pharynx and soft palate (Von Lunteran E and Strohl KP. The muscles of upper airways. 1986.). They also distinguish nocturnal snoring without apnea episodes. However, most authors tend to support the opinion that this form is just an early stage of SAS development (Sielber A.P., 2007).
How can I cope with this problem?
Many scientists and doctors have been actively speculating on this issue. The arsenal of methods is rather extensive — starting from choosing for patient the optimal position in bed, use of intra-oral devices and equipment that generates constant positive pressure, up to oxygen therapy and even surgical treatment (including plastic repair of soft palate). They also try to treat the SAS by means of drug correction. However, none of the afore-listed methods is 100% effective.
In our opinion, one of the methods that will help restore the tone of muscles of the upper respiratory tract is the Ujjayi-pranayama, that is, keeping the muscles of naso-, oro- and laryngeal pharynx in the tightened (toned) state during the process of inspiration and / or expiration.
The regular practice of Ujjayi-pranayama shall form a fairly stable muscular stereotype and cause training of oral and nasal pharynx’ muscles.
Moreover, in scope of conscious performance of Ujjayi simultaneously with full yoga-breath we can speak about harmonious and deliberate involvement into breathing process of all respiratory muscles in proper sequence, and thus about stimulation of Betzinger center’ neurons and development of correct neuro-muscular stereotype.
Therefore, simultaneous regular practice of Ujjayi-pranayama together with full yoga-breath can come as a considerable support in treatment of snoring with or without episodes of sleep apnea. The application of these pranayamas in yoga-therapeutic complex can facilitate the patient’s recovery.
It is also worth mentioning that in case of patients suffering from snoring the airway obstruction (the blocking, from of lat. obstructio — a hindrance, obstacle) is localized both behind the posterior veil of the soft palate and the soft palate (velopharynx) and the back of the tongue (oropharynx), or in different combinations of the first two. Rarely they also observe the collapse (the deflation, from the Lat. collapsus — fallen, deflated) of the airway detectable at the level of epiglottic cartilage, but it is not specific to patients with obstruction (Rubinstein I, Slutsky AS, Zamel N, and Hoffstein V., 1988, S. L . Babak, Institute of Pulmonology).
The performance of Ujjayi-pranayama only on inspiration or only on expiration shall respectively tone up nasopharynx and oropharynx. In this case we shall have more sophisticated and more effective tools for working with patients suffering from SAS.