Rest

Throughout all nature we observe the phenomena of universal rhythm, manifested in opposing forces, such as heat and cold, light and darkness, construction and destruction, etc. The human body is as much affected by this rhythm as is any other form of life.

Opposing Forces In Nature

There are two forces continually at work within us, one toward destruction and disintegration, and the other toward construction and upbuilding. The common physiological terms for these activities are "waste" and "repair," and we observe them as one of the distinct manifestations of the universal laws of growth, progress, and evolution.

History moves in cycles. Even the life of nations depends somewhat upon this same principle of the interplay of the positive and negative forces of life.

We see the same thing in the changes of the seasons upon the face of the earth. Throughout autumn and winter there is a process of decay, death, and disintegration; leaves fall; plants and vegetables die; fruits ripen, fall and decay. This process continues until former beautiful and symmetrical bodies of matter are thoroughly disintegrated, and the particles once composing them are separated into their original elements, to be appropriated in new manifestations of life in springtime and summer.

We are inclined to think of the human body as a machine - a marvelous, intricate, and complex mechanism which serves our will and our desires; as a tool with which we work out our earthly destiny. But, unlike man-made machines, it is self-repairing, self-adjusting, and contains within itself the forces of construction, which are constantly tending toward perfection, while our industrial machines are constantly tending toward their own disintegration and destruction.

Life And Death In Changes Of Seasons

Human body compared to a machine.

Every movement of the body, conscious or unconscious, even thought and emotion, use up some part of the body-tissue which must be replaced by new material. This constant change in the texture and the make-up of the body we call "metabolism," involving the functions of digestion, absorption, assimilation, and elimination.

While we may regard the body as a machine, there are many points in which the favorite comparison to a steam-engine is not exact.

Constant Changes In Body-Tissue

The inert metal composing the steam-engine has no power in itself, nor does power act through the different particles of metal, but it is controlled by the external application of force, which is the result of chemical changes caused by combustion in the fire-box. The metal of the engine has no part in the production of this energy. It does not need to take periods for rest, and if it were possible to supply it continually with water and fuel, it could run steadily from the time it was started until one or more of its essential parts were destroyed through friction.

Favorite Comparison Of The Body With The Steam-Engine

But the engineer and the fireman who drive the engine find it necessary to rest from their labors at certain intervals, not merely for fuel and water, but to prevent serious destruction of body-tissue. This is true because man is compelled by hitherto unrecognized laws to give his body an opportunity, not only for readjustment in its composition, but also for the actual renewal of that power which animates him and makes him an intelligent, self-adjusting, and self-controlled being.

Necessity for rest.

The Old Physiology

According to the teachings of the old physiology, our stomachs were fire-boxes of the human engine; food was fuel, and the stomach was supposed to transform this fuel into work or energy by a process not entirely clear. Just as it is impossible for the lifeless iron and steel, within itself to transform coal and water into dynamic power, and to apply that power to its own locomotion, so it is impossible and entirely incompatible with reason for mere muscular tissue of the body to extract enough energy from the food we eat to perform the work necessary for that transformation itself, besides enough more to carry on all the functional activities of the system, and at the same time to do hundreds of foot-tons of physical labor. In this fact lies the key to some understanding of the phenomenon of rest and sleep.

The Stomach As A Fire-Box

The old physiology was really never able to explain how it was possible for the digestive apparatus to extract, from the amount of food consumed, the enormous amount of energy which the average person expends each day.

Phenomenon of rest and sleep.

Rest And Recreation

These terms are often confused. When one is engaged in some occupation or activity other than his regular vocation, it is commonly called "recreation." This is a misconception, because it is merely a change in activity and must also be more or less destructive to other sets of nerves or muscular tissue. It is not in reality recreation - it simply throws the life-power into a new channel, which is more responsive, and calls for less action from those parts of the mechanism which have been employed in the work from which one is seeking relief. It is for this reason that we find some pleasure in a new and different activity, though it, too, may be destructive to the human cell.

Change Of Occupation Not Recreation

One may alternate from one kind of activity to another indefinitely, which would be better than no change, but the human mechanism would finally give way under such violation of fundamental law. The mental worker may change, however, to any manual labor requiring little thought, and the physical worker to some form of mental labor, with far better effect. But, in our present civilization, specialization has become so far advanced that the physical laborer is seldom qualified for mental work, and the mental worker has almost neglected manual training.

Specialization in business not conducive to health.

True rest and recreation is found in mental tranquility and sleep.

Sleep

From observation and study of the state we call sleep, we notice that as night approaches and the activities of the day wear upon us, both the nervous and the muscular organisms relax, so that it becomes more and more difficult to maintain a positive and an active attitude of mind. There is a tendency toward cessation and rest, which gradually brings upon us that passive condition called sleep.

In spite of the fatigue often experienced before we retire, we awake again on the morrow with renewed strength and power. From these and other reasons we are led to believe that during the hours of activity the body is constantly expending vital energy in both internal and external work, and that during the hours of sleep, through some unknown process, the body is charged with vital energy which is stored up and used gradually for carrying on the various functions and activities of the system.

Evidence Of Acquired Energy During Sleep

Just what this energy is, just where it comes from, just how it is stored, just the manner in which it is delegated to the body, we cannot say. We can only observe its workings, or effects, and formulate therefrom a theory. We are led to believe, however, that this energy is stored in the nervous organism, perhaps most largely in the brain, as brain tissue is the last to break down or waste away in sickness, ill health, disease, or starvation, often maintaining its full weight up to the point of death.

The Mystery Of Energy

Even in sleep the expenditure of energy in the vital processes continues vigorously, depending upon conditions immediately preceding sleep, but usually in a much more passive degree than in the waking hours. These activities, however, are no more pronounced in their constructive action or repair, than in ordinary periods of rest during the waking hours.

Vital processes expend energy during sleep

Some Reasons

The processes of nutrition, alone, demand the expenditure of much energy, and the degree of energy available from foods, even by perfect combustion, would yield but a fraction of the energy expended by the body.

The average laborer in shoveling coal, swinging an axe or a pick, expends energy far in excess of the amount that could possibly be obtained from his food. A day laborer may eat a piece of beefsteak, two or three potatoes, and a few slices of bread, and will shovel twenty tons of earth to a height of five feet; a Japanese soldier will carry a heavy load and walk all day, subsisting only on a handful of rice, and besides this, will do some thinking, which consumes energy.

Food furnishes but a fraction of the total body-energy.

Energy required for work in excess of energy obtained from food

We also have on record fasts, of from thirty to forty days, which, in some cases, show a slight gain in strength. There are also hundreds of students of natural living who adopted the "no breakfast plan" and again many, only one meal a day, limiting their consumption of food to comparatively small quantities of nuts, fruits, and vegetables, who have found thereby a remarkable increase in vitality, strength, and general physical and mental power.

Evidence gained from "fasts" and "no breakfast" plan.

Since the processes of nutrition, including digestion, circulation, assimilation, and excretion consume energy, and notwithstanding this we are able to perform hundreds of foot-tons of labor a day besides; since we have found it possible to continue to live, and in some cases to even increase the amount of strength and work-power on a very limited diet; since it is a mathematical impossibility to produce as much energy from the food consumed as the body expends, we are forced to the conclusion that we do not obtain all our energy from food. Therefore, from a careful analysis of the phenomenon of sleep, we conclude that it is very closely connected with this mystery.

Relation of sleep to expenditure of energy

Oxidation And Air

One of the most important of the vital functions is breathing. Physiologists, teachers, and lecturers continually remind us of the comparative time we could live without food or water, and the remarkably short time we could live if entirely deprived of air.

Relative Importance Of Air, Food And Water

Oxygen is vitally necessary for the purpose of purifying the blood and supplying the various tissues and fluids in the body, of which oxygen forms an important constituent. However, oxygen is not the only necessary element which is utilized by the system in the process of breathing, as human beings die immediately upon being placed in a receptacle of undiluted oxygen. Just what this other factor is, science has not clearly defined, but that it is concerned with rest and sleep we have at least unconsciously recognized, as showm by our often referring to periods of rest as "breathing spells"; from the fact that we have found it of great importance to keep the air we are breathing moving constantly about us, especially while asleep. From all these facts we are forced to believe that sleep plays an important part in producing and maintaining body-energy, besides constantly recharging the system with oxygen.

Oxygen not the only required element in breathing.