“No physical endowment is of more importance for a long and a vigorous life than capacious lungs. The intensity and efficiency of an individual’s life depend very largely upon the amount of air he habitually passes in and out of his lungs, just as the intensity of a fire, granting plenty of fuel, depends upon the rate at which the air is brought in contact with the fuel. It has been found that lung capacity depends very largely upon the height; thus, the taller a person the greater his lung capacity, other things being equal. The following table shows the lung capacity, or rather the amount of air which can be forced out of the lungs, the so-called vital capacity, for men of different heights:

Height
Inches
Weight
Pounds
Vital Capacity
Cubic Inches
64115205
65126228
66126230
67133244
68134248
69140254
70141256
71150272
72151287

“The proper time for the development of the chest is in childhood and in youth. The best of all means for increasing the chest capacity is running and active sports of all sorts. Mountain climbing, going up and down stairs, and all kinds of exercises which produce strong breathing movements are effective means of chest development. Exercises of this nature are far superior to breathing exercises, so-called, of whatever sort. Breathing exercises in which the lungs are forcibly compelled to take in more than the ordinary amount of air very soon become tiresome. The effort is wholly voluntary, and the muscles soon weary. When, however, a thirst for air is created by some active exercise which fills the blood with carbonic-acid gas, so that deeper and more rapid breathing is necessary to rid the body of this poisonous gas and to take in a supply of oxygen in its place, the act of breathing is no longer difficult, embarrassing, or tiresome, but is, on the other hand, a pleasure and a gratification. The impulse which comes from within, from the so-called respiratory centers, so excites the respiratory muscles that they cause the chest to execute the strongest breathing movements with the greatest ease, ventilating every portion of the lungs, filling every air-cell to its utmost capacity.

ONE OF THE
TRAILS UP WHICH THE HOPIS CLIMB AT FULL SPEED.

“Runners always have large and active chests, whereas sedentary persons have chests of limited capacity and rigid walls. When a chest is not stretched to its utmost capacity many times daily, it rapidly loses its flexibility. This is especially true after the age of thirty. In persons who have passed middle life, the rigidity of the chest is so great that there can be no very considerable increase in size. By development of the respiratory muscles the chest capacity may be to some degree increased, but the proper time for chest development is in childhood and youth. At this period, also, the integrity of the heart renders possible without injury those vigorous exercises which are essential to secure the highest degree of chest development.

“Probably the best of all exercises for the development of the chest and breathing powers is swimming. The position of the body, the head held well back and the chest well forward, and the active movements of the arms and limbs render swimming a most efficient breathing exercise. The contact of cold water with the skin also actively stimulates the movement of the chest, while at the same time it renders possible prolonged and vigorous muscular movements by increasing the energy and activity of the muscles.

“Special breathing exercises, as well as those active muscular movements which induce a thirst for air, are beneficial to the lungs by maintaining the flexibility of the chest, strengthening the respiratory muscles, and ventilating the lungs. These movements also exercise a most extraordinary beneficial effect upon the stomach, liver, and other organs which lie below the diaphragm. Each time the diaphragm contracts, it gives the liver, stomach, and adjacent organs a hearty squeeze, so to speak, emptying out the blood contained in these parts as one may by compression empty a moist sponge. All movements which increase the strength of the abdominal muscles are an important means of aiding and improving the breathing function.”

From this it will be seen, therefore, that everything that prevents the full and free exercise of the lungs, especially in the lower portions, is of direct injury to the body. Men need all the lung capacity and power they can gain in order to sustain their energy in the battle of life; and women, especially young women, who are to become the future mothers of the race, should be taught that the art of healthy, deep breathing is one of the fine arts, and the most important one that they can learn.