In the CHAPTER SIX The physiological effects of meditation
Meditation is a most powerful way of controlling physiological processes and also of controlling physiological reactions to psychological events. One of the most profound changes that takes place in the body during meditation is the slowing down of the metabolism, the rate of breaking down and building up the body, for there is a sharp reduction in oxygen consumption and carbon dioxide output. Experimenters have measured up to a 20 percent decrease in oxygen consumption, which is because the respiration rate is slower. The reduced metabolic rate is due to the control over the involuntary nervous system which one develops through meditation.
Meditation has a noticeable influence on blood pressure, which drops much lower than normal both during and after meditation, and, therefore, meditation can be particularly recommended for those people suffering from high blood pressure. The heart rate also slows down to a few beats every minute. Another interesting discovery regarding the blood system is the fact that the blood flow increases during meditation. To explain this we must again bring in the autonomic nervous system and, in particular, the sympathetic nerve network. This network, as one of its many functions, constricts the blood
vessels and in turn the blood flow. The greater the constriction, the less the blood flow. During meditation the activities of the sympathetic system are reduced and therefore constriction of the blood vessels is automatically decreased, resulting in a greater flow of blood.
This increased blood flow greatly benefits the meditator. For example, let us consider lactate production. Lactate is a substance produced mainly in the muscles when there is no free oxygen. It is profusely produced during periods of intense activity when the muscles are performing extensive work. A so-called energy debt is incurred because the muscles must expend more energy than the oxygen supply to the muscles allows for. Now lactate is produced to provide for the much required extra energy.
During periods of rest, lactate is slowly broken down into other substances, since enough oxygen is now being supplied to the muscles. In meditation, the increased blood flow ensures that oxygen is more efficiently delivered to the muscles and that lactate is more quickly and effectively removed. The reader should note that in meditation, total intake of oxygen is actually less; what is increased is the distribution of available oxygen to the muscles where it breaks it down the lactate. At the same time, intake of oxygen into the cells during the metabolic process is reduced. Production of lactate is stimulated by the sympathetic nervous system; inhibition of the sympathetic nervous system during meditation automatically reduces production of the lactate.
Why is the subject of lactate production so important? Because medical tests show that persons suffering from anxiety, neuroses or tension have a high level of lactate compared to when they are calm and tranquil. When lactate is injected into the body in scientific experiments, there is a sudden and marked increase in the level of anxiety. Also, people suffering from high blood pressure have markedly more lactate in the body than people with normal blood pressure and those who meditate regularly.
Meditation is the perfect method of reducing the lactate level and consequently reducing blood pressure and all types of anxiety symptoms. Remember also, that anxiety is the cause of many of the so-called physical ailments, as well as innumerable mental diseases. Meditation is the method of treating these diseases, by doing away with their root cause. This is far preferable to the present widely adopted cures which treat the symptom and not the underlying cause.
How do these physiological changes compare with other forms of relaxation, such as sleep and hypnotism? There appears to be little or no correspondence whatsoever. During hypnotism there is little or no change in the metabolic rate, and in sleep the physiological changes take place normally after some hours. In meditation the ratio of oxygen to carbon dioxide in the blood (not the quantity) remains reasonably constant. During sleep there is a noticeable build-up of carbon dioxide in the blood.
The fight or flight body defence mechanism
The fight or flight defence system of the body is the
sympathetic nervous system and the adrenal glands. The activities of the sympathetic nervous system and adrenal glands have been known for quite some time; these two systems complement each other. During times of stress, danger or fear, the adrenal glands secrete a hormone called adrenaline, which prepares the body for fight or flight. It makes the body more efficient. It increases the heart rate, increases the respiration rate, improves eyesight, hearing, etc., as well as inhibiting the digestive functions so that the energy can be more usefully employed to face threatening situations. This system is for short-term dangers. For threats that last a longer period of time, the sympathetic nervous system takes over and keeps the body at a continuous higher level of intensity. Eventually, however, when the threat has disappeared the body functions return to their usual level of activity.
The stressful, competitive, modern way of life is such, however, that many people almost continually operate at a high level of preparedness for fight or flight. It may be from fear of the boss, fear of losing respect in the eyes of friends and neighbours, fear of not being able to pay all the hire purchase bills, and so on. Under these conditions, the individual is always tense, liable to large fluctuations of moods and is almost in a continual state of dissatisfaction and general unhappiness. The body also loses its ability to resist disease.
Many persons may say or think that they are relaxed for most of their lives. For some this may be true but for many, scientific tests will conclusively show that they are almost constantly tense, though they are not aware of it. In
reaction to various situations, even of an inconsequential nature, they tense their muscles, squint their eyes, bite their nails or whatever. This type of action is so habitual that they are not aware they are doing these compensatory activities.
These habitual reactions are the forerunner of psychosomatic diseases. When a person is manifesting these tensions, whether he knows it or not, he is really preparing himself for the fight or flight reaction; the reaction that the sympathetic nervous system and the adrenal glands are designed to bring about. These actions are small and insignificant in external appearance, but they indicate that changes in heart rate, blood pressure, etc., are taking place internally. This prolonged stimulation of the adrenal and sympathetic system can lead to the so-called civilized ailments such as high blood pressure, diabetes, coronary thrombosis, peptic and duodenal ulcers, together with a large number of mental diseases, as well as backache, skin problems, muscular twitches and a host of other ailments.
The only sure method of counteracting, preventing and curing these ailments is to completely relax the whole body and mind every day. Sleep, of course, is the usual way, yet most people are so tense that they don’t even relax during sleep. They are still trying to solve their daily problems while sleeping. Sleep is generally insufficient to relax, balance and eradicate the damaging effects of the overuse of the adrenal and sympathetic systems. It is only during deep relaxation that the body processes can finally recuperate themselves and return to their normal level of
activity. Meditation is a means to do this. In a sense, meditation can be regarded as the counterpart or the counterbalance to the sympathetic nervous system and the adrenal glands. It is a panacea for modern life. It is the sure means of attaining positive health of the whole mind-body complex.
Not only must we learn to relax, we must also change our response to our surroundings. The happiness of each person depends on harmonization and integration with the environment, not on being in perpetual fear of the environment. The mind-body system must be reprogrammed so that the adrenaline is not squirted into the blood at every possible situation. We must reprogram our body and mind so that the reaction is different, so that the individual can relax, be happy and start to raise the level of his awareness.
So that the reader can appreciate the importance of changing the mind, we will give a brief explanation of the mechanism of the brain which is concerned with making us tense or relaxed. An important part of the brain is the limbic system. This system, which is situated at the top of the brain stem, has the function of comparing sense data from the sense organs with the information that is already in the brain from previous experiences in life. In other words, the limbic system compares data stored in the brain (our memory) with the incoming sense data; it analyzes them in terms of previous experiences.