Breathing divides into inspiration and ex piration. Inspiration (breath taking) is in stinctive and involuntary. The latter is like the former, but it is greatly amplified and ex tended. Our attention now goes to voluntary inspiration. Its primary physical act is expan sion of the diaphragm. Evidence of that is dis covered wherever that organ connects with outer parts of the chest, in the generous ex pansion of those parts, and by quite a little expansion of parts of the body below the dia phragm. The latter action is caused by the pressure of the centre of the diaphragm (quite in the middle of the body) downward upon the abdominal viscera. Deep breathing, or taking large draughts of air, is always accompanied by generous spread of the body at the level of the diaphragm, and considerable spread of the por tion just below that level. Few adults will do this upon the first attempt at mental direction of inhalation, because they have lost the natural habit. If they will study for a few minutes quiet instinctive (not directed) breathing, they will find they really do breathe as described above. But this is not enough for °breathing for health.° It must be amplified through mental direction; on the line of instinctive breathing, only much more extensively.
The custom of taking deep breath can be developed into habit in a short time, and it should be used daily. Direct the thought during inhalation to generous expansion of the body in the neighborhood of the diaphragm, and after such expansion has begun, enlarge the sides and back above the diaphragm. Fill the lungs fully, retain the air a few seconds and exhale com pletely. Such complete exhalation implies that breath shall be forced out by drawing in the abdomen. After repeating the act of inspiration and expiration four or five times, which, by the way, should never be done violently, one can feel the more active rush of blood through the body. This demonstrates that the cleansing process of the circulatory system is accomplish ing its work. When a good glow is established refrain from further exercise for the time, but resume it when quietness is apin restored. Five or ten minutes given to this practice every morning and evening will, in a month, establish physical strength. Followed through a term of years it will rebuild the body and make it almost invulnerable against the attack of disease. Persons with weak lungs or sluggish circulation can, by this means, become rugged and very active. So far-reaching is the result that great physical strength is acquired. Even the usually expected elements of decay, as manifested in carious teeth and falling hair, are arrested or prevented. The success of all physical treat ment lies in the regularity and persistence with which it is followed. In a few weeks or even in one week, the benefit will be observed, but the rebuilding of a body requires persistent prac tice for a year at least.
Practice of the above nature increases the lung space. Probably no new air-cells can be created, although some authorities claim that there are. The expanding power of existing air-cells is enlarged, and the muscles which cause the expansion greatly increase their power. Such expansion can be measured. It is well to take the bust measure, passing the tape-measure around the body just below the arm pits, and take measurement on the first day of each month thereafter. Comparison with previous measure will show constant in crease for a full year. How great an increase to expect depends upon the person. From two
to five inches in a year is usual. A more per fect measure of development is given by the spirometer which, as its name implies, is a breath-measure. It records the vital capacity of the lungs. Test measurements in over 500 students proved that every one gained in size of lungs, and many made marvelous changes in their physical condition. The spirometer records the cubic inches of air space in the lungs. Such capacity varies in accordance with the height, and is greater in men than in women. Tall people have largest lungs, ordinarily, and those who are slim, rather than stout, increase most through practice. Records show that the increase in air capacity in one year averages from 25 to 33 per cent. All this has direct bearing on health. In the lungs the air-cells are surrounded by minute blood vessels. All the blood, after its course through the body, passes to the lungs to discharge its gatherings and to receive the supply of oxygen necessary for life. It is evident that if the air supply is increased 25 per cent, cleansing and oxygenation take place more quickly and more thoroughly. It is recognized among physicians that the purity of the blood is the most important ele ment in keeping well. Meeting the attack of bacilli is the triumph of medical science. The germ of disease is found in the blood, and in modern science inoculation for destroying such germ is the keynote. In the practice of breath ing every individual has nature's method of doing what medical science does. It goes be yond that, in that breathing provides prevention as well as cure. The ounce of prevention is the most valuable. Disease germs can hardly find lodgment, and they certainly cannot propagate, in a body which is perfectly well. A feeling of lassitude and ((run down° is the admonition which shows that germs are at work. Your doctor tells you to take long walks in the open air. He says in other words that oxygen must be supplied to the lungs. Much surer are we to respond to health-laws if such training as all can have has made the taking of large draughts of air possible.
Above is described inhalation and exhalation. While no attempt has been made to formu late a complete system of training, enough has been said to show what may be done. At first, daily practice should be gentle. This will bring into correct use all physical organs which gov ern breathing. When one realizes ease in action he should make the dual act of inspiration and expiration more generous. Expiration should now be made more complete. That is, make exhalation forceful by drawing in the abdom inal muscles and lower ribs greatly. This will also cause broader inspiration. Thus the two sets of muscles will be powerfully increased, and the expanding power of the lungs will be enlarged.
When breath is imbibed in large quantities it should be retained a little time that it may purify the blood. Three or four seconds are long enough at first, but the time may be in creased gradually until one can hold it 30 or more seconds. The physical act of holding the breath consists of arresting the inspiratory mus cles when they have drawn breath in and re fusing to allow them to return to their relaxed position. The very act of thus commanding adds to their strength. It is one of the con tributing factors toward strengthening the whole body. The tendency of modern life to greater physical activity accentuates the need of symmetrical development of the lungs and their controlling forces.