This section is from the book "The Power Of Concentration", by Theron Q. Dumont. Also available from Amazon: The Power of Concentration.
Lie down and thoroughly relax your muscles. Concentrate on the beating of your heart. Do not pay any attention to anything else. Think how this great organ is pumping the blood to every part of the body; try to actually picture the blood leaving the great reservoir and going in one stream right down to the toes. Picture another going down the arms to the tips of the fingers. After a little practice you can actually feel the blood passing through your system.
If, at any time, you feel weak in any part of the body, will that an extra supply of blood shall go there. For instance, if your eyes feel tired, picture the blood coming from the heart, passing up through the head and out to the eyes. You can wonderfully increase your strength by this exercise. Men have been able to gain such control over the heart that they have actually stopped it from beating for five minutes. This, however, is not without danger, and is not to be practiced by the novice.
I have found the following a very helpful exercise to take just before going to bed and on rising in the morning: Say to yourself, "Every cell in my body thrills with life; every part of my body is strong and healthy." I have known a number of people to greatly improve their health in this way. You become what you picture yourself to be. If your mind thinks of sickness in connection with self you will be sick. If you imagine yourself in strong, vigorous health, the image will be realized. You will be healthy.
 
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