A little child is an object lesson in alternating exercise, sleep, and food. Almost every waking moment a child is squirming, twisting, and turning, using every muscle of his little body, particularly every vital organ. No excess of waste accumulates in his tissues. The adult does not, as a rule, twist or turn or freely stretch the muscles of the vital organs. The child and the animal stretch and yawn to start the circulation whenever they awaken from sleep. This is instinct—Nature’s law. Man jumps out of bed and begins dressing with mind bent on the business of the day.
The necessity of oxygen is evident. The body will subsist about forty days on the food stored within it without resupply, but it can endure only a few seconds without oxygen, because heat, occasioned by the chemical action of oxygen, is necessary to keep up the physical activity termed “life.” Carbon dioxid (carbonic acid gas) accumulates and poisons the system.
The necessity of habits of full, correct breathing cannot be too fully emphasized.
The quantity of oxygen daily consumed should equal the sum of all other food elements.[8]
Oxygen is necessary in the combustion of fats, starches, and sugars, as it is necessary in the combustion of carbon in wood or coal, and, as explained on pages [123] and [124], oxygen is necessary to keep the body warm.
Deep breathing aids digestion and assimilation, not only because of the regular exercise given to the pancreas, the spleen, the stomach, and the liver by the correct movement of the diaphragm, but also because of the latent heat which the oxygen liberates within the digestive organs and out among the tissues.
While the chemical action of food creates activity within, this activity is materially aided by exercise. Exercise and oxygen are also necessary for chemical action in tearing down waste and in putting raw material into condition to be appropriated to the body needs.
Two glasses of water in the morning and fifteen minutes of brisk exercise in well-selected movements, to start a forceful circulation and to surge the water through the digestive organs, are a daily necessity if one is to keep clean and strong within.
Exercises should be interspersed with deep breathing of pure air.
In breathing guard against drawing up the chest; make the muscular effort, while practicing full breathing, to expand the entire rib cage, back, front, and side.