Scientific Qi Exploration-12

Part 12: Qigong and the Cardiovascular System

Marty Eisen Ph. D.

1.  Introduction

The effects of Qigong on blood pressure appear in Section 2.  Section 3 presents studies on heart rate and rhythm.   Cardiac output effects appear in Section 4.  Some results for heart output and blood supply of the whole body appear in Section 5.  Section 6 describes effects on the microcirculation.  The alterations in the blood supply to the brain and its vessels are explored in Section 7.  Finally, the effect on rapid, large changes in altitude appears in Section 8.  These physiological effects depend on the type of Qigong, the intensity of practice, and the level of expertise of the practitioner.

2.  Effects on Blood Pressure

Chinese researches have been treating hypertension using Qigong for about 50 years.  Thirty-two patients, intolerant to anti-hypertensive drugs, were treated at the Shanghai Institute of Hypertension by practicing Qigong for 6 months.  A 1959 report concluded that their symptoms were somewhat improved (1).  Another study was conducted in 1962 on the effects of Qigong on 415 hypertensive subjects.  The conclusion was that 80.5%, who practiced Qigong regularly, and 17% of those practicing irregularly maintained a stable blood pressure (1).

Another impressive study (2), because of its time extent and number of participants was also carried out at the Shanghai Institute of Hypertension.  Subjects were randomly divided into a Qigong group (n = 122) and a control group (n = 120) of non-practitioners.  Standard hypertensive drugs were given to both groups.   The patients were observed for 30 years.  At the end of this time, 47.76% of the control group had died, but only 25.41% of the Qigong group had died.  The incidence of stroke in the Qigong and control groups was 20.49% and 40.83%, respectively.  The incidence of death due to stroke in the Qigong and control groups was 15.57% and 32.50%, respectively.  All of these results were statistically significant.  Ultrasound diagnosis on 40 patients revealed that members of the Qigong group had stronger heart muscles and better left ventricular function.

A similar 6- year study with 204 hypertensive subjects was conducted at Xiamen University in Fujian Province.  It concludes that a combination of hypertensive drugs and Qigong was 19% more effective than the drugs alone.  The mortality rate from all causes was 17.33% and 32% in the Qigong and control groups, respectively.  After 6 months of practice, the Qigong practitioners’ blood contained higher levels of “good” high-density lipoprotein cholesterol and had less of a tendency to form clots than the control group’s blood.  The qigong group was also less reactive to stress, with more stable blood pressure (3).

A 1991 research concluded that Qigong practice didn’t influence normal systolic pressure but could increase a low diastolic pressure to its normal value.  Further research showed that Qigong had a homeostatic effect, restoring balance from either direction, by improving dysfunctions of the nervous system (1).

Another study on the blood pressure of 312 patients, using Health Qigong, was conducted in 2002.  After six months, subjects were reported to have decreased blood pressure both while resting and practicing Qigong.  These results were more pronounced in patients consistently practicing Qigong, compared to those who did not (1).

A combination of Qigong and biofeedback was used at the Research Institute of Traditional Chinese Medicine, Tianjin, to treat 639 primary hypertensive patients.  Some patients had a significant drop in blood pressure after only one session.  Most patients had a significant drop in blood pressure after 8 weeks.  The combined therapy was effective for 85.13% of the patients.  Most patients followed 3 years did not have access to the biofeedback equipment.  However, those who still practiced Qigong, 97.7% had stable, lowered blood pressure (4).

Another modern method for lower blood pressure by squeezing a hand-held device is described in (5).   Blood pressure can also be lowered by a simple breathing exercise, which can be aided by a timing device suitable for patients who can’t concentrate (6).

The Dean of the Beijing Medical School reported in (7), that Tai chi students have lower blood pressure. Greater cardiac efficiency, as measured by a treadmill test and less abnormal EKG patterns than controls.  Other research on the benefits of Tai Chi for the cardiovascular system can be found in (8).

Breath holding or inspiring longer for longer periods than expiring can raise ones blood pressure.  This can be dangerous as shown by the following case study (9).   A sixty-five year old woman was an avid Qigong practitioner to regulate her blood pressure.  After practicing Qigong one morning, she had a stroke.  She gradually improved in the hospital, stopped practicing Qigong, and eventually recovered.  She wanted to practice Qigong again.  For safety, her blood pressure was monitored every 3 minutes during one of her Qigong exercises. In the first three minutes of exercise, her blood pressure increased and remained at an unusually high level for approximately the next thirty-five minutes.   It was thought that this was the result of the type of Qigong practiced, which consisted of many isometric elements while holding ones breath.

The study (8) suggests that patients with hypertension should only practice Qigong under the supervision of a physician.  They also suggest that hypertensive patients should not practice breath holding while exercising.

3.  Effect on Heart Rate and Rhythm

Qigong has a homeostatic effect on heart rhythm.  Research (1) has shown that proper Qigong practice by patients with paroxysmal supraventricular tachycardia decreased their heart rate from 180-200 beats per minute (bpm) to 70-80 bpm.  The heart rate of sinus bradycardia patients would rise to normal limits after practicing Qigong.

Research by Cao et al, published in 1989, studied the heart rate of Qigong practitioners on reaching tranquility (1).  After 20 minutes their heart rate decreased statistically significant from an average of 83.5 bpm to 75.3 bpm, and decreased further to 71.2 bpm after 30 minutes.  The hear rate decrease lasted for 20 minutes after stopping Qigong.  The hear rate of the control group also decreased but was not statistically significant.

Proper Qigong practice can regulate cardiac dysrhythmias such as: premature ventricular contraction, bigeminy, trigeminy, pre-excitation, and conduction block (1).  Premature ventricular contraction (PVC) is an early depolarization beginning in the ventricle instead of the usual place, the sinus node. They are very common, and are sometimes perceived as a palpitation. They often occur without the patient being aware of it at all. By themselves, PVC’s do not present any problem.  Ventricular bigeminy is the occurrence of a PVC every other beat; trigeminy is every third beat. The main point with these types is that the PVC’s are more frequent, but are otherwise little different from PVC’s.  Ventricular tachycardia is defined as three or more consecutive PVC’s. This may extend for hours. If it is prolonged and at a high enough rate, it can be serious.  However, some people who have these frequently and tolerate them for years.

Normally, the atria and the ventricles are electrically isolated.  The electrical contact between them exists only at the atrioventricular node.  The normal electrical depolarization wave is delayed at the  atrioventricular node to allow the atria to contract before the ventricles.   In all pre-excitation syndromes, at least one more conductive pathway is present.  There is no such delay in an abnormal pathway.  Hence, the electrical stimulus passes to the ventricle by this tract faster than via normal atrioventricular system.  Therefore, the ventricles are depolarized (excited) before (pre-) normal conduction system.

A simple breathing exercise may also alleviate arrhythmias (6).

4.  Cardiac Output Effect

Cardiac output is the volume of blood ejected by the left ventricle into the aorta in one minute.  During the practice of Relaxing Quiescent Qigong the cardiac output declines, probably because of the lower energy consumption.  However, research shows that this effect may not be permanent.  Once again, Qigong has a homeostatic effect.  Cardiac output eventually decreases for those Qigong practitioners with previously high values and increases for those with previously low levels (1).

In a 2006 paper Du et al used an ultrasonic Doppler diagnostic device on 39 subjects practicing Muscle/Tendon Changing Qigong.  After 6 months of practice, they discovered that the blood volume per heartbeat, ejection fraction (the percentage of blood ejected from the left ventricle with each heart beat), and cardiac output of the subjects increased in a statistically significant way (1).

5.  Effect on Pulse and Total Blood Supply

Once of the first things beginners notice when first starting Qigong is that their fingertips pulsate.  This blood flow phenomenon has been used to measure Qigong proficiency.  Twenty-two Qigong practitioners and five controls had their fingertip blood flow measured by a laser microcirculation flow meter, while sitting quietly, at the Beijing University of Aeronautics and Astronautics.  There was a statistically significant increase in blood flow in the Qigong group, but no significant change in nth control group.  When 10 subjects were given 5 sessions more of Qigong training, their new test results were much higher than previously (10).

While practicing Quiescent Qigong, there is a decrease in the pulsations of the temporal artery and an increase in the resistance of the cerebral vessels, besides the fingertip pulsations.  This reduction in cerebral blood flow shows an alteration of blood flow in the body (1).

Hand warming often accompanies fingertip pulsations.  Some individuals can learn to warm their hands at will.  This technique can sometimes result in alleviating migraine headaches and other vascular diseases.  Voluntary hand warming was also proposed to allow air force mechanics to work under frigid weather conditions.

The photoelectric earlobe sphygmograph measures blood volume by passing a light beam through the earlobe.  Decreased light intensity results from increased blood volume and is displayed as a higher amplitude in the graph on the sphygmograph screen.  This device was used in an experiment by researchers from 3 major Chinese laboratories (11).  The peripheral blood flow was measured during 48 subjects’ waking state and during Qigong meditation.  The average amplitude of the sphygmograph wave increased significantly by 30% during Qigong practice, as compared to just being awake.  In 8 subjects the amplitude increased over 100% and seemed associated with the ability to enter a deep state of Qigong tranquility.

TCM pulse diagnosis is done by palpating 3 locations on both wrists over the radial artery:  Cun (Inch): distal or front at the wrist crease, Guan (Bar): middle, just medial to radial styloid, and Chi (Cubit): proximal or rear.  An experienced practitioner can determine the state of the body and its  organs, according to TCM theory.  According to TCM theory “The slippery pulse comes as soon as Qi arrives and disappears as soon as Qi goes away.”  Research shows that during Qigong practice subjects usually had a slippery pulse.

The TCM pulses of 2 Qigong Masters were measured using an electropulsograph while one practiced Internal Nourishing Qigong and the other a hard, martial art type.  They were asked to direct Qi to the chest, upper and lower abdomen and a variance in the related pulse locations was observed.  The variances in the hard Qigong Master were more significant than those observed in the Internal Nourishing Qigong Master (1).

These results suggest a method of exploring the connection between qigong and TCM theory.

6.   Effect on Microcirculation

Microcirculation is the blood flow between micro-arteries and micro-veins (capillaries).  Studies show that Qigong practice can improve practitioners’ microcirculation by changing blood viscosity, increasing elasticity of blood vessels, controlling platelet concentration, accelerating blood flow, raising skin temperature, and increasing the number of micro blood vessels.  In 1966, Huang found that cancer patients practicing Guo Lin Qigong increased the microcirculation in their lungs (1).

Other research indicates that the percentage of hypertensive patients suffering from abnormal microcirculation via capillary loops in a nail bed is 67%, much higher than normal, but this abnormality is reduced to 31% after practicing Qigong.  Qigong also reduces thickened artery vessels (1).

The change in nail microcirculation was observed for normal subjects after 30 days of Qigong training in another experiment.  Before training, 42 out of 154 observed capillaries were crossed and 34 we deformed.  After Qigong practice, the number of crossed and deformed capillaries was reduced by 14.3% and 11.2%, respectively.  The speed of blood flow was also increased (1).

7.   Effects on Elasticity of Cerebral Vessels and Blood Supply

The rheoencephalogram (REG) is a graphic registration of the changes in conductivity of tissue of the head caused by vascular factors.  Qigong can improve both the elasticity of cerebral blood vessels and cerebral circulation as shown by REG measurements (1).  This may be some of the reasons for Qigong’s ability to improve memory, delay senility, prevent cerebral disorders and increase longevity.  Brain cells may live longer if they have a better supply of oxygen.

Greater cerebral blood flow may also improve intelligence as shown by the following experiment.    In a fourth grade, 85 boys and 85 girls were divided into 4 groups.  Two groups did Qigong abdominal respiration while quietly sitting for 2 minutes before each class every day.  The control groups were not given any Qigong training.  After 6 months, the test scores in language mathematics, and geography increased by 11.95% in the Qigong groups, but did not change significantly in the control groups (12).

8.   Effect on large, Rapid Changes in Altitude

Research (13) has been done to determine if Qigong would protect pilots from altitude stress.  A group of 32 young men did Qiyuan Qigong for 4 weeks, while a control group of 34 young men did exercise to music.  The two groups rapidly ascended into the Tibetan highlands from a low altitude.  Before and after entering the highlands, symptoms of altitude sickness and physiological

Parameters were recorded.  The Qigong group suffered less altitude stress according to measurements of blood pressure, heart rate, oxygen consumption, micro-circulation on the tongue tip and nail bed, and temperature at the left Laogong point (Pericardium 8).

References

[Dr. Eisen is a retired scientist, who constructed mathematical models in medicine. He has studied and taught Judo, Shotokan Karate, Aikido, Qigong, Praying Mantis Kung Fu, and Tai Chi in different places.  He took correspondence courses in Chinese herbology and studied other branches of Chinese medicine with a traditional Chinese medical doctor.  He was the Director of Education of the Chinese Medicine and Acupuncture Institute in Upper Darby, PA.]