Scientific Qi Exploration, Part 11
Qigong and the Respiratory System
Marty Eisen Ph. D.
An outline of respiration will be given to help understand some of the presented topics. The muscles used for breathing are the diaphragm, which separates the abdominal and thoracic cavities and the intercostals muscles. Inspiration occurs when these muscles contract. Contraction of the diaphragm moves it downward, increasing the vertical dimension of the thoracic cavity, while the contraction of the intercostal muscles elevates the ribs and sternum, increasing the front- to-rear dimension of thoracic cavity. Hence, the volume of the thoracic cavity is increased and so lowers air pressure on the lungs, which allows air to move into lungs. Relaxation of these muscles reduces the volume of the thoracic cavity and so increases the pressure on the lungs and air is exhaled.
Oxygen and carbon dioxide pass in and out of cells by diffusion, which depends upon their partial pressure PO2 and PCO2, respectively. Blood returning from the body to the lungs, via the alveolar capillaries has higher PCO2 and lower PO2 than the inspired air in the alveoli and so CO2 diffuses into the alveoli to be expired and O2 diffuses into the capillaries, to be carried by the blood to the cells. The higher PO2 and lower PCO2 values in the alveoli are the result of breathing in more O2 than CO2 and expiring CO2.
The oxygenated blood is carried to the cells by the systematic capillaries, maintaining the partial pressures of O2 and CO2. Oxygen diffuses from the blood into the cells, while carbon dioxide diffuses from the cells into blood, since working cells utilize O2 and produce CO2.
About 95% of the CO2 generated in the tissues is carried in the red blood cells. Only about 5% of the CO2 generated in the tissues dissolves directly in the plasma. It is hypothesized that CO2 enters (and leaves) a blood cell by diffusion through the plasma membrane assisted by facilitated diffusion through transmembrane channels in the plasma membrane. Once inside, about one-half of the CO2 is directly bound to hemoglobin at a site different from the one that binds oxygen. The rest is converted by the enzyme carbonic anhydrase into bicarbonate ions and hydrogen ions. The bicarbonate ions diffuse back out into the plasma. The hydrogen ions bind to the protein portion of the hemoglobin. Hence, there is no effect on pH, which keeps the body from becoming dangerously acidic.
Only 1.5% of oxygen carried in the blood is dissolved in the plasma; 98.5% is bound to the hemoglobin. The relationship hemoglobin saturation (the percentage of hemoglobin molecules carrying oxygen) and PO2 is important one, because hemoglobin carries most of the oxygen in the blood and allows the percentage of O2 released to be calculated. The graph of this function is called the oxygen-hemoglobin saturation curve. Hemoglobin saturation increases with PO2 but levels off, to reach its asymptotic value of 100%. For example, at a PO2 of 40 mm. Hg., which is the average pressure in cells in a resting person, the hemoglobin saturation is about 75%. This means 25% of hemoglobin molecules release oxygen in the systemic capillaries. However, if activity is increased and cells need more oxygen, hemoglobin molecules have 75% more oxygen to provide. Suppose activity is increased and the PO2 in the active cells is 20 mm. Hg. Then, the corresponding hemoglobin saturation is about 25% and so 75% of hemoglobin molecules release oxygen in the systemic capillaries (see the diagram).
Active cells produce more CO2 which combines with water to produce carbonic acid; also more heat is produced. PO2 decreases which causes red blood cells to increase production of the compound 2,3-diphosphoglycerate. Intuitively, the hemoglobin saturation should decrease for a fixed PO2, since more O2 should be released for the active cells. This is actually how the oxygen-hemoglobin saturation function behaves. Lower pH, increased temperature, more 2,3-diphosphoglycerate, and increased levels of CO2, give a lower value of hemoglobin saturation for any given PO2 value.
The respiratory rate is controlled by centers in the brain as well as chemoreceptors. The rhythmicity center of the medulla controls automatic breathing. The apneustic center and the pneumotaxic center, both located in the pons, promote inspiration and inhibits inspiration, respectively. There are also chemoreceptors located in aorta and carotid arteries and in the medulla. These are influenced more by increased CO2 levels than by decreased O2 levels and> stimulate the rhythmicity center resulting in an increased rate of respiration.
The respiratory rate is also increased by vigorous exercise. The exact explanation is not known, but it is not the result of increased production of CO2. Since the scientific interpretation of Qi is controversial, the following modern definition has been adopted. Qigong is a body-mind exercise that integrates body, mind, and breath adjustments into one (1). An important component of this definition is breathing adjustments. First, the effects of breathing on the autonomic nervous system will be discussed. Section 3 investigates the movement of the diaphragm. The effects of Qigong on the frequency, rhythm, and depth of respiration appear in Section 4. Next, Qigong’s relation to respiratory functions and illnesses are described. How Qigong reduces the number of free radicals and so might prevent some diseases, including cancer, is discussed in Section 6. Finally, some effects of left, right and alternate nostril breathing are presented.
2. Autonomic Nervous System Effects
Inspiration increases the activity of the parasympathetic nervous system. This will decrease the heart rate; lower the blood pressure; increase saliva secretion, alimentary tract movement, and bladder contraction. Expiration increases the activity of the sympathetic nervous system. This will increase the blood pressure; decrease saliva secretion and GI motility, and dilate the pupils of the eyes (1). Other effects of activating the autonomous system can be found in (2).
Thus, adjustment of breathing can influence the tissues, glands and organs of the body via the autonomic nervous system. For example, there are Qigong exercises for treating hypertension, enlarged prostate and heart arrhythmias. These require several steps which must be learned and usually a Qigong teacher is required. All of these methods have the common feature of adjusting the breath. There is a simpler technique for these problems that requires little study and can usually be mastered alone. It only involves adjusting the respiration rate and is described in (3).
Joint research, conducted by the University of California and the Shanghai Qigong Research Institute in 2004, provides another illustration of the effects of breathing on the autonomic nervous system (1). A metronome was used to synchronize subjects’ respiratory frequency. Both the respiration and heart rate were recorded simultaneously. Calculations of the variance of respiratory and heart rate frequency showed that they were identical with each other. A stable respiratory frequency induced a stable heart rate with the same variance.
Conversely, improper breathing patterns can have adverse health effects. For example, a hypertensive person, who normally inhales longer than he exhales, will tend to raise his blood pressure.
3. Diaphragmatic Effects
The amplitude of the diaphragm’s movement, as observed by x-rays, is enlarged in experienced breathing exercisers. For example, the amplitude of diaphragmatic movement, for some practitioners of Internal Nourishing Qigong, was about 150mm. This is 3–4 times as great as normal (1).
Another research project measured the amplitude of the diaphragmatic movement of a tuberculosis group when breathing deeply. It averaged 29.7mm. After two months of Qigong practice it averaged 59.7mm (1).
In another experiment for treating bronchial asthma and chronic bronchitis subjects practiced Relaxation Qigong (Fang Song Gong) and Lesser Heavenly Circulation (Xiao Zhou Tian). After gaining some proficiency, fluoroscopic observation showed that the movement of their diaphragms significantly increased while practicing qigong. In addition, their respiratory frequency (number of breaths per minute) decreased (4). Some subjects’ respiratory frequency was reduced to 2–3 breaths/min. while practicing the Lesser Heavenly Circulation (also called Small Circulation Qigong or Microcosmic Orbit) (1).
The normal respiratory rate in adults ranges from 14 – 16 breaths per minute, but is greatly reduced for experienced Qigong practitioners while practicing. Hence, the energy expended is less than in normal breathing, even though the diaphragm has a greater displacement. Coupled with the fact that the larger displacement of the diaphragm allows greater oxygen absorption and carbon dioxide expulsion, more energy is produced during Qigong practice, than when resting and breathing normally. Additionally, the greater movement of the diaphragm produces a stronger massaging effect on abdominal viscera, which aids both digestion and elimination.
4. Effects on Frequency, Rhythm, and Depth of Respiration
Normally, an adult’s respiratory frequency can range between 12–18 breaths per minute. It depends on the person’s condition and posture. Energy and oxygen consumption vary when standing, sitting, and lying, being less when lying. Intentionally reducing the respiratory rate, even if lying and only for a few minutes, results in
During static Qigong in the seated position subject’s respiratory frequency is reduced to 4–5 breaths/min. Skilled practitioners can exhibit very slow respiratory rates between 1–2 breaths per minute, or even lower (1). They are relaxed and no discomfort is exhibited at this low respiratory frequency. This is the result of other physiological changes induced by Qigong.
During Qigong practice, the maximal ability to move gas in and out of lungs, usually quantified by measuring maximum expiratory flow rates (ventilatory capacity) can be about 28% lower due to the decrease of the respiratory frequency. However, the tidal capacity (the amount of air your lungs hold during normal breathing) can average about 78% higher because of the increase in respiratory depth (1). Moreover a higher uptake rate of oxygen is observed. Hence, the saturation of blood oxygen is maintained at a physiological level or higher, which provides better conditions for cells to take in sufficient oxygen. Thus, experienced Qigong practitioners won’t suffer hypoxia from low respiratory rates.
5. Qigong Effects on Respiratory Functions and Illnesses
Other parameters, besides the ventilatory and tidal capacities, are used to study lung function. Some examples are: (forced) vital capacity – the maximum amount of air a person can expel from the lungs after a maximum inspiration, timed vital capacity – the maximum amount of air during a forced vital capacity determination that can be expelled in a given number of seconds, maximal ventilatory volume – the maximal amount of air that a person can breathe in or out in a short period of time, typically 10, 12, or 15 seconds but recorded as the volume in 1 minute. The Total lung capacity is the volume of air in the lungs after the deepest inhalation.
Airway or respiratory (tract) resistance (also called impedance) is the opposition to flow caused by the forces of friction. It is defined as the ratio of driving pressure to the rate of air flow. If the pressure varies with time, the average pressure is used when a single value is given. Admittance is the reciprocal of the resistance.
In 2002, the Shanghai Qigong Research Institute studied the changes in respiratory function of 312 Health Qigong practitioners at two six month intervals. The results of the two tests showed that their vital capacity, timed vital capacity, and maximal ventilatory volume all increased significantly. The first-second exhaling speed of practitioners over 60 also increased significantly (1). These results indicate that regular Qigong practice not only increases lung volume and respiratory capacity, but also improves the common syndrome of respiratory deterioration related to aging.
The forced respiratory gas flow rate capacity (The modern terminology might be maximal ventilatory volume.) and respiratory tract impedance were tested in bronchial asthmatics before and after Qigong practice. The forced tract impedance was significantly reduced and the forced respiratory gas flow rate capacity was significantly increased (1). The findings, indicating improvement in respiratory function, provides evidence that Qigong for treatment of bronchial asthma was effective.
Capacity tracing equipment was used to measure respiratory gas flow rates, intrapleural pressures, and thoracic gas volumes for a Qigong and control group of 7 subjects by Corey (1). Using these measurements, respiratory tract impedances were calculated. Then, the ratio of admittance to thoracic gas volume, called the admittance ratio, was calculated before and after Qigong practice. The Qigong group’s admittance ratio rose quickly by 12.1% , on average, to about 20% at the end of the practice. Though dropping quickly after Qigong practice, the admittance ratio was still 8% higher than the control group. The control group’s admittance ratio remained the same. These results suggest that Qigong can improve respiratory function. Since there were only a small number of subjects, larger scale experiments should. Sun Yinxing et al. (5) studied changes in respiratory function of 14 elderly patients suffering from respiratory or cardiac disease after 18 months of practicing Tai Chi and Qigong (5). Their vital capacity, total lung capacity, and forced vital capacity significantly increased on the average by 3.31%, 7.34%, and 18.11 %, respectively. Although there were a small number of subjects and no control group, the improvements in lung function deserves further study.
The effect of 3 months of Qigong combined with standard drug therapy for 20 chronic respiratory patients was investigated by Li Ziran et al (6). The control group consisted of 10 subjects taking only drugs. The combined therapy was more effective in improving symptoms, energy, appetite, and sleep. During the course of treatment, the combined therapy group’s breathing rate decreased significantly, on the average, from 19.3 breaths per minute to 6.6. The breathing rate of the controls only went, on the average, from 20.1 to 18.2.
Hua Huang (7) used Relaxation Qigong, quiet breathing, two or three times daily for 20 t0 30 minutes, self-massage, concentrating on acupoints, and other such techniques to treat bronchial asthma. All 99 patients practiced seated to lessen the chances of an asthmatic attack. Drugs were only used for acute attacks. These treatments were administered from one to two months. Improvement was measured by the five following criteria: decreased frequency, severity and duration of asthmatic attacks, less usage of drugs, and increased capacity for physical work. Four years later 30 patients had no attacks for at least one year. Twenty-four improved in more than two of the five criteria. No change or improvement was exhibited by 6 patients.
Decreased vital capacity was directly associated with increased mortality in the Framingham Study on risk factors for heart disease (8). Another long research project on risk factors for longevity concluded that vital capacity was more significant in predicting longevity than cholesterol, smoking or insulin metabolism (9). Qigong’s ability to increase vital capacity may be another reason that Qigong may increase the chance for a longer life.
6. Qigong and Free Radicals
Free radicals are unstable atoms, molecules or ions with an unpaired electron in their outermost or valence shell. To regain stability free radicals seize electrons from stable molecules causing cell damage, which may lead to cancer, more rapid aging and other degenerative diseases.
Normal metabolism creates certain harmful byproducts, such as, free radicals. The production of these radical can be increased by physical (working too hard, insufficient rest or illness), mental or environmental (pollutants) stress.
To combat these radicals the body produces antioxidant enzymes – such as: glutathione peroxidase, superoxide dismutase, methione reductase and catalase, which neutralize them.
However, the body can be unbalanced by illness or stress and the high demand for antioxidants cannot be met.
One solution is to use antioxidant supplements (Vitamins A, C, E; selenium and germanium), antioxidant enzymes, or coenzyme Q10.
Another cheaper and readily available solution is to practice stationary, deep breathing exercises as in some forms of Qigong. This will produce an increased demand for oxygen which is taken up from the blood by a cell. Free radicals are neutralized by combining with the oxygen molecules. Thus, the daily practice of quiet Qigong can enhance your health
The exact explanation of why slow, deep breathing alone can increase the oxygen level in the blood and the uptake level is not known. Some research on these facts appears in (10) and (11).
Some forms of Qigong reduce stress and so reduce the number of free radicals. Other types of still Qigong decrease the uptake of oxygen because they reduce metabolic activity and so reduce the production of free radicals. In fact, some practitioners can almost completely eliminate their need for food (Bigu) or sleep and greatly reduce their need for air, without any ill effects (12).
Some forms of Qigong may enhance the body’s production of antioxidant enzymes and so promote health. For example, some experiments have been conducted to measure levels of superoxide dismutase (SOD) in subjects practicing Qigong. SOD protects cells from the free radical superoxide. One trial consisted of 200 subjects, ranging from 52 to 76, divided into a Qigong and a non-practitioner group, each composed of 50 men and 50 women. The Qigong group practiced E Mei Nei Gong, Liu Bu Yang Sheng Gong, relaxation and self massage for at least a half an hour per day for about one year. SOD levels increased significantly in the Qigong group compared to the control group (13). Another research project (14) also found a significant increase in SOD levels in116 subjects after practicing Qigong for two months.
More research on Qigong’s effects on other antioxidant enzymes produced by the body is required.
Since free radicals can be neutralized by combining with oxygen molecules, why not breath rapidly and forcefully (hyperventilate)? Hyperventilation can result in paresthesia in the hands, feet and lips, weakness, shortness of breath, dizziness, lightheadedness, headache, chest pain, slurred speech, , and sometimes fainting Although the concentration of O2 in the blood is increased, the concentration of CO2 is drastically reduced and the blood becomes more alkaline or the pH is increased. Thus, the hemoglobin saturation is increased and less O2 will be released for use by cells.
7. Effects of Left, Right and Alternate Nostril Breathing
Breathing through the left, right or alternating nostrils is used in some forms of Qigong but is more commonly practiced in Yoga Breathing (Pranyama) exercises. Ancient texts mention 72,000 subtle channels (nadis) in which prana (vital energy) flows. Two main channels are the ida and pingala nadis. The ida and pingala run from the left and right sides, respectively, of the Muladhara (Base Chakra or energy center) near the base of the coccyx to the Sahasrara (Crown Chakra near the posterior fontanelle at top of the head. These nadis enter each of the chakras on one side and emerge from the other side as they coil their way to the crown of the head. At the Ajna chakra, positioned between the eyebrows, Ida and Pingala send branches to the left and right nostrils, respectively.
Ida is white, feminine, cold, represents the moon and is associated with the Ganges River. Pingala is red, masculine, hot, represents the sun and is associated with the Yamuna River.
Ultradian rhythms are an important characteristic of the autonomic nervous system (ANS). These occur because one branch of the sympathetic nervous system (SNS) dominates one side of the body, and one branch of the parasympathetic nervous system (PNS) dominates on the opposite side, and then the two systems switch dominance periodically on the two sides. This leads to lateralized rhythms of the ANS and their respective innervated organs and structures, including the cerebral hemispheres (15).
The nasal cycle is the alternating obstruction of the left and right nostrils. It is a physiological condition resulting from activation of one half of the ANS by the hypothalamus and is not pathological nasal congestion. This cycle, known long ago by Yogis, was first described by the physician Richard Kayser in 1895 (16). Research indicates that the nasal cycle closely mimics the ultradian rhythm of alternating cerebral hemispheric activity. Its period ranges from 25–340 minutes while awake and from 25–300 minutes while asleep. The left nostril is more open and the right more congested when the right hemisphere of the brain is more active and is associated with increased activity of the PNS. The right nostril is more open and the left more congested when the left hemisphere of the brain is more active and is associated with increased activity of the SNS.
Studies have also shown that these lateralized ultradian rhythms are also tightly coupled to the ultradian rhythms of the neuroendocrine, cardiovascular, and fuel-regulatory hormone (insulin) systems. Recent research comparing plasma catecholamine levels in the venous circulation of both arms, while resting, found that that the norepinephrine levels alternated with the rhythm of sympathetic dominance of the nostrils (15).
In the 1960’s, Kleitman proposed the Basic Rest-Activity Cycle (BRAC) hypothesis for studying psychophysiologial states. It was based on how rapid eye movement and non-rapid eye movement sleep were coupled to ultradian variations in physiological activity. However, it did not integrate the observations on the lateralized activities of the ANS and the central nervous system. A new hypothesis takes these observations into account. The nasal cycle is used as marker for psychophysiological states. Right-nostril breathing dominance marks the activity phase of the BRAC and more SNS activity; left-nostril dominance marks the rest phase of BRAC and increased PNS activity (15).
Different physiological states are associated with dominance of one or the other nostril. For example, deep sleep is initiated quicker with left nostril dominance since PNS activity is enhanced. Left nostril, right brain dominance, is better for receiving new ideas, while right nostril, left brain dominance is advantageous while talking. The right side of the brain is more intuitive and creative. The speech center is located in the left hemisphere for right-handed and most left- handed people.
Autism and early language impairment may be associated with left handedness and left eye preferences. The patients with autism had no normal nasal cycle and probably had almost continuous left nostril breathing dominance (15).
Consciously breathing through one nostril can be used to induce different physiological states. Increasing the flow of air in the right nostril stimulates the sympathetic nervous system and so increases the heart rate, produces more sweaty palms, dilates the pupils, opens up the lungs, etc. Increasing the flow of air through the left nostril stimulates the parasympathetic nervous system and so increases digestion, lowers the heart rate, relaxes muscles, etc. (17). Practicing alternate nostril breathing can balance both of these systems brain activity. The pattern of “thought waves” can be changed by consciously altering nasal dominance by forced nostril breathing using the congested nostril (18).
Left hemispheric stimulation, by 20 minutes of forced unilateral right nostril breathing, led to a significant bilateral decrease of 25% in intraocular pressure in 46 patients with open and closed angle glaucoma (19).
Some obsessive compulsion disorders are associated with an abnormal nasal cycle and have been treated by Yogic breathing techniques (20).
108 school children, ranging from 10 to 17 years, were randomly assigned to four groups. Each group practiced: (i) right nostril breathing, (ii) left nostril breathing, (iii) alternate nostril breathing, or (iv) breath awareness without manipulation of nostrils. These techniques were practiced for 10 days. Verbal and spatial memory was assessed initially and after 10 days. An age-matched control group of 27 were similarly assessed. All 4 trained groups showed a significant increase in spatial test scores at retest, but the control group showed no change. Average increase in spatial memory scores for the trained groups was 84%. It appears yoga breathing increases spatial rather than verbal scores, without a lateralized effect. Spatial & verbal cognitive tasks, are supposed to be right and left brain functions, respectively!
130 right hand dominant, school children between 11 and 18 yrs of age were randomly assigned to 5 groups. Each group had a specific yoga practice in addition to the regular program for a 10 day yoga camp. The practices were: (1) right-, (2) left-, (3) alternate- nostril breathing (4), breath awareness and (5) practice of mudras (yogic hand gestures). Hand grip strength of both hands was assessed initially and at the end of 10 days for all 5 groups. The right-, left- and alternate-nostril breathing groups had a significant increase in grip strength of both hands, ranging from 4.1% to 6.5%, at the end of the camp though without any lateralization effect. The breath awareness and mudra groups showed no change. Hence, these results suggest that yoga breathing through a particular nostril, or through alternate nostrils increases hand grip strength of both hands without lateralization (22).References 1. Liu, T. and Chen, K. Eds. Chinese Medical Qigong. Singing Dragon, London, 2010. 2. Eisen, M. Scientific Exploration of Qi: Effects of Qigong on the Nervous System. Part 9(a): The Nervous System. Qi Dao, Nov./Dec., 2009. 3. Eisen, M. Qigong Breathing Exercises for Hypertension, Enlarged Prostate and Arrhythmias, http://www.altmd.com/Specialists/Arch-Acupuncture-Health-Center/Blog/Qigong-Breathing-Exercises-for-Hypertension-Enlarg 4. Hua Huang et al. Further experiments in treating bronchial asthma and chronic bronchitis with the aid of several new testing methods. First World Conf. for Academic Exchange of Medical Qigong, Beijing. 93-95, 1988. 5, Sun Yinxing et al. The role of Qigong and Taijiquan in respiratory rehabilitation. Ibid, p. 101. 6. Li Ziran et al. An observation on the results of drug and Qigong therapy for chronic respiratory diseases. Ibid, pp. 109-12. 7. Hua Huang. An approach to the treatment of bronchial asthma by Qigong. First Int. Seminar on Qigong, pp. 92-3, 1986. 8. Gordon, T. and Kannel, W.B. The Framingham Study. An epidemiological –investigation of cardiovascular disease. Nation-al Lung and Heart Institute, Betheseda MD, Section 1-26, 1970. 9. Cullen et al. Multiple regression analysis of risk factors for cardiovascular disease and cancer mortality in Busselton, west Australia: a 13 year study. J. of Chronic Diseases, 36, pp. 371-77, 1983. 10. Soust, et al. Blood flow to the respiratory muscle during hypercapnic hyperpnoea in the newborn lamb, Respiratory Phys., 76(1), pp. 93-105, 1989. 11. Chinet, A.E. and Mejsner, J. Is resting muscle O2 uptake controlled byO2 availability to the cells< J. of applied Phys., 66(1), pp. 253-60, 1989. 12. Green, E. and Green, A. Beyond Biofeedback. Delacorte Press, New York, 1977. 13. Xu Hefen, et al. Clinical study of the anti-aging effects of Qigong. Second World Conf. for Academic Exchange of Medical Qigong, Beijing, p. 137, 1993. 14. Ye Ming et al. Relationship among erythrocyte superoxide dismutase (RBC-SOD) activity, plasma sexual hormones (T, E2), aging and Qigong exercise. Third International Symposium on Qigong, Shanghai, p. 32, 1990. 15. Shannahoff-Khalsa, D. S. Selective Unilateral Autonomic Activation: Implications for Psychiatry. CNS Spectr. 12(8), pp 625-34, 2007. 16. Kayser, R. Die exakte Messung der Luftdurchgängigkeit der Nase. Arch. Laryng. Rhinol., Berlin, 8, p 101, 1895. 17. Shannahoff-Khalsa, D.S. and Kennedy, B. The effects of unilateral forced nostril breathing on the heart. Int-J-Neurosci., Nov; 73(1-2), pp 47-60, 1993. 18. Shannahoff-Khalsa, D.S. Rhythms of the mind and breath, advances. J. of Mind-Body Health, 6, 2, pp 51-5, 1989. 19. Backon, J. et al. A functional vagotomy induced by unilateral forced right nostril breathing decreases intraocular pressure in open and closed angle glaucoma. Br. J. Opthalmol. Oct;74 (10), pp 607-9, 1990. 20. Shannahoff-Khalsa, D.S. and Beckett, L.R. Clinical case report: efficacy of yogic techniques in the treatment of obsessive compulsive disorders. Int-J-Neurosci., Mar; 85,(1-2), pp 1-17, 1996. 21. Naveen K.V. et al. Yoga breathing through a particular nostril increases spatial memory scores without lateralized effects. Psychol Rep, Oct, 81,2, pp 555-61, 1997. 22. Raghuraj, P. et al. Pranayama increases grip strength without lateralized effects. Indian J Physiol Pharmacol, Apr, 41,2, pp 129-33, 1997. .
[Dr. Eisen is a retired scientist, who constructed mathematical models in medicine. He has studied and taught Judo, Shotokan Ka-rate, Aikido, Qigong, Praying Mantis Kung Fu, and Tai Chi in different places. He took correspondence courses in Chinese her-bology and studied other branches of Chinese medicine with a traditional Chinese medical doctor. He was the Director of Educa-tion of the Chinese Medicine and Acupuncture Institute in Upper Darby, PA.]
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