The lungs should be allowed the greatest freedom possible. Their capacity is developed by free action; it diminishes if they are cramped and compressed. Hence the ill effects of the practise so common, especially in sedentary pursuits, of stooping at one's work. In this position it is impossible to breathe deeply. Superficial breathing soon becomes a habit, and the lungs lose their power to expand. A similar effect is produced by tight lacing. Sufficient room is not given to the lower part of the chest; the abdominal muscles, which were designed to aid in breathing, do not have full play, and the lungs are restricted in their action.
Thus an insufficient supply of oxygen is received. The blood moves sluggishly. The waste, poisonous matter, which should be thrown off in the exhalations from the lungs, is retained, and the blood becomes impure. Not only the lungs, but the stomach, liver, and brain are affected. The skin becomes sallow, digestion is retarded; the heart is depressed; the brain is clouded; the thoughts are confused; gloom settles upon the spirits; the whole system becomes depressed and inactive, and peculiarly susceptible to disease.-- MH 272, 273.
Constant Supply of Fresh Air -- The lungs are constantly throwing off impurities, and they need to be constantly supplied with fresh air. Impure air does not afford the necessary supply of oxygen, and the blood passes to the brain and other organs without being vitalised. Hence the necessity of thorough ventilation. To live in close, ill-ventilated rooms, where the air is dead and vitiated, weakens the entire system. It becomes peculiarly sensitive to the influence of cold, and a slight exposure induces disease.-- MH 274.
Oxygen in the Lungs -- It is essential to health that the chest have room to expand to its fullest extent in order that the lungs may be enabled to take full inspiration. When the lungs are restricted, the quantity of oxygen received into them is lessened. The blood is not properly vitalised, and the waste, poisonous matter which
should be thrown off through the lungs is retained. In addition to this the circulation is hindered, and the internal organs are so cramped and crowded out of place that they cannot perform their work properly.-- MH 292.
Voice Training a Part of Physical Culture -- Next in importance to right position are respiration and vocal culture. The one who sits and stands erect is more likely than others to breathe properly. But the teacher should impress upon his pupils the importance of deep breathing. Show how the healthy action of the respiratory organs, assisting the circulation of the blood, invigorates the whole system, excites the appetite, promotes digestion, and induces sound, sweet sleep, thus not only refreshing the body, but soothing and tranquilising the mind. And while the importance of deep breathing is shown, the practise should be insisted upon. Let exercises be given which will promote this, and see that the habit becomes established.
The training of the voice has an important place in physical culture, since it tends to expand and strengthen the lungs, and thus to ward off disease. To ensure correct delivery in reading and speaking, see that the abdominal muscles have full play in breathing, and that the respiratory organs are unrestricted. Let the strain come on the muscles of the abdomen, rather than on those of the throat. Great weariness and serious disease of the throat and lungs may thus be prevented. Careful attention should be given to securing distinct
articulation, smooth, well-modulated tones, and a not-too-rapid delivery.
This will not only promote health, but will add greatly to the agreeableness and
efficiency of the student's work.-- Ed 198, 199.