December 7, 2022


The Roles of Rest and Sleep in Supplying Body Needs
1. Introduction
Rest and sleep are two essentials of life that have an importance unrecognized by most people. Sleep and rest are indulged because the need for them overtakes rather than because of an enlightened awareness of their role in well-being.
This lesson endeavors to teach the physiological bases for rest and sleep. Their significance can then be better appreciated.
Sleep is an infant science in that it has not been long studied. The 50 to 100 sleep researchers in this country think of themselves as pioneers, and in a sense they truly are. Also, they are medically oriented, as are most people, unfortunately. Now, about 30 years after sleep research began, sleep researchers have uncovered relatively little knowledge of what sleep is about. However, they do occasionally unearth a gem or two of useful knowledge.
The restorative roles of rest and sleep are everywhere admitted, but the physiological mechanisms are not clearly understood by researchers. Hopefully this lesson can prove not only enlightening but also furnish you guidance you can turn to benefit for yourself and your clients.
2. What Is Rest?
Rest is a period of inactivity during which the faculties can restore expended nerve energy. When we create wastes faster than our body can eliminate them and deplete our energies faster than our faculties can restore them, a period of inactivity enables the body to catch up on its homework. Physical and mental inactivity can be called rest.
There are many different kinds of rest. Some are:
Physiological rest , during which the body and most of its faculties are inactive, as in sleep and in fasting.
Sensory rest , during which time the nervous system and brain are relaxed or not normally exerted, as in fasting, sleep and meditation. The eyes are closed in sleep and meditation, which curtails a great drain of energy.
Emotional rest , as in withdrawal from the affairs and excitants of daily life that draw upon our nerve energies.
Mental rest , as in eschewing those affairs that demand our attention and thoughts.
Essentially, rest is the curtailment of energy expenditure and waste generation. This permits the body to redirect energies to cleansing and restoration.
2.1 Relaxation as Rest
To relax means to cease or decrease exertion. The word has broad connotations, and recreation or play might be called relaxation. Generally, relaxation means to let go of that which stresses the body and to undertake a course that does not tense or stress. Relaxation is a variant form of rest.
2.2 Only the Body Needs Rest
The cells of the body require rest but not necessarily sleep, but the brain and nervous system sleep. Cells require periodic rest so that they may cope with their eliminative and restorative functions.
2.3 Rest is Incidental to Sleep for the Most Part
Many people are apt to confuse the words rest and sleep as being synonymous. Rest, as we have seen; means cessation of activity. Sleep necessarily implies rest due to the immobilization of the body, but the condition of sleep exists only when consciousness has ceased. However, we should note that not all forms of unconsciousness are sleep. Coma, catalepsy and stupor must not be confused with sleep.
3. What Is Sleep?
Our foremost sleep scientists have not settled upon an answer to this question. Obviously sleep is loss of consciousness. But what more is there to it? Why should awareness cease? Does not the brain conduct millions of processes continuously even though it has lapsed into unconsciousness?
Sleep scientists have several theories about what sleep is: One is that the neurons become fatigued and simply lower their activities below the level required for consciousness. Another is that the brain inhibits the reticular activating system.
Another theory is that the brain and nervous system operate on nerve energy, a form of electricity. The body, like an electric car, needs to be recharged at night. Sleep is a partial shutdown for recharging.
3.1 Why Should We Sleep At All?
Dr. Nathaniel L. Kleitman of the University of Chicago has concluded that the body generates nerve energy during sleep and that we sleep for this purpose. All other writers and researchers observe and attest to the restorative powers of sleep but do not suggest the physiological basis for these powers.
Among the texts you have is Better Sleep for a Better Life . This book details many particulars on the whyfore and conditions of sleep. We shall not repeat them here. We sleep because the brain requires, we may presume, a state of unconsciousness for the regeneration of nervous energy.
3.2 The Purpose of Sleep
Experiments with electrosleep indicate that the body generates low-level electricity during sleep. So far, researchers have not discovered where the body stores its electricity.
The primary purpose of sleep seems to be the generation of nerve energy. That seems to be the only reasonable explanation, for most researchers agree that sleep is a restorative. The vitality of the organism is restored under the condition of sleep.
Guyton’s Textbook of Medical Physiology takes the position that sleep occurs because of neuronal fatigue. He says that, when one of the millions of parallel neurons in the feedback circuits falls out of activity, the lowered level of excitability of other neurons starts a chain of depressed activity that results in sleep. More particularly, wakefulness is attributed to the excitability of the reticular activating system, which is, a network of neurons, and sleep is attributed to lack of excitability.
Perhaps this does chronicle the mechanism of sleep, but other passages in the same physiology text appear to negate this position. Nerves or neurons perform twenty-four hours daily, just as the heart muscles. They need no rest or sleep. Only a certain part of the brain needs sleep, for the brain and nervous system continue to conduct millions of processes under the condition of sleep.
It appears that the faculty of wakefulness must cease in sleep and that neurons are only partially inactivated. Moreover, it is known that the brain is active during sleep except for those areas of the brain involved with consciousness. Some body processes are conducted more vigorously in sleep than in wakefulness.
Guyton is unable to explain what causes fatigue in neurons since, in theory, they are not subject to fatigue. He says: “We still need to explain the cause of fatigue of neurons after 16 hours of wakefulness and their recovery of excitability after 8 hours of sleep.” Perhaps the depletion of nerve energy causes fatigue in neurons.
Sleep is primarily for the purpose of generating nerve energy or low-level electricity. Many other beneficial purposes are also served during sleep. The physiological rest obtained during sleep is extraordinarily valuable. During the prolonged rest of sleep, the body restocks its cells and organs with fuel, replaces cells that have lost their vitality and rids itself of extraordinary toxins that may have been uneliminated the previous day. Thus, the value of sleep is manifold.
The benefits of sleep may be chronicled as follows:
The regeneration of nerve energy;
Refueling the liver and cells with glycogen;
Destruction of old cells and replacement with new cells (Multiplication of cells occurs during sleep at a rate of more than twice that during waking hours); and
The body expels more debris and wastes during sleep and rest than when active.
Undoubtedly there are other benefits of sleep, but these are the salient ones. For instance, the body uses less nerve energy and generates less waste when asleep.
3.3 Sleep as an Essential of Life
We can accept sleep as being absolutely necessary without question. But, as well, getting enough sleep is an essential of life. It is impossible for a healthy person to oversleep but undersleeping is an evil of our, times—a transgression most of us commit against ourselves.
When we undersleep, not enough nerve energy is generated to meet needs. We use more nerve energy when we are awake longer and generate less with less sleep, other conditions being equal. When our nerve energy is squandered to meet excessive consciously-directed activities, then nerve energy for unconscious body activities is not available. This may mean poorer digestion, impaired elimination and so on—the body must suffer generally.
With adequate sleep enough nerve energy is generated to meet our normal needs. The question of what constitutes adequate sleep and how to best obtain it is very important. The book, Better Sleep for a Better Life treats this subject in depth. In this lesson we’ll endeavor to explore other materials to reinforce the wealth of observations in that book.
To read more see Lesson 15 of the Life Science Course here:…/permalink/3326522010758117