THE MUSCLES.
_The Muscles--Flexion and Extension--The Tendons--Contraction--Physical
Strength--Necessity for Exercise--Its Effects--Forms of
Exercise--Walking--Riding--Gymnastics--Open-air
Exercise--Sleep--Recreation._
[Sidenote: 1. What are the muscles? Their number? The design of most of
them? Of a few?]
1. THE MUSCLES.-- The great mass of the body external to the skeleton, is
composed of the flesh, or _Muscles_, which largely determines its outline
and weight. The muscles are the organs of motion. Their number is about
four hundred, and to each of them is assigned a separate and distinct
office. They have all been studied, one by one, and a name given to each,
by the anatomist. Each is attached to bones which it is designed to move. A
few are circular in form, and enclose cavities, the size of which they
diminish by contraction.
[Illustration: FIG. 8.--MUSCULAR TISSUE.
_a_, _b_, Striped muscular fibres: _c_, The same more highly magnified.]
[Sidenote: 2. The structure of flesh? Its color, etc.? The composition of
the fibres? How marked?]
2. If we examine a piece of flesh, we observe that it is soft, and of a
deep red color. Its structure appears to be composed of layers and bundles
of small fibres. Let us further examine these fibres under the microscope.
We now discover that they are, in turn, made up of still finer fibres, of
_fibrillæ_: these are seen in Fig. 8. The fibres are beautifully {26}
marked by parallel wavy lines, about ten thousand to an inch, which give
the fibre its name of the _striped_ muscular fibre. All of the voluntary
muscles present this appearance.
[Sidenote: 3. Arrangement of the muscles? Their action? Flexion and
extension? Action of the muscles when we stand erect?]
3. FLEXION AND EXTENSION.--The muscles are, for the most part, so arranged
in pairs, or corresponding sets, that when motion is produced in one
direction by one set, there is, opposite to it, another muscle, or group of
muscles, which brings the limb back to its place. When they act
alternately, a to-and-fro movement results. When a joint is bent, the
motion is called _flexion_; and when it is made straight again, it is
called _extension_. When both sets act equally, and at the same moment, no
motion is produced, but the body or limb is maintained in a fixed position:
this occurs when we stand erect. The muscles which produce extension are
more powerful than those opposite to them.
[Illustration: FIG. 9.--A, Biceps muscle of the arm: B, C, Its tendons.]
[Sidenote: 4. Kinds of muscles? The voluntary? Involuntary? The heart? Give
the example. The hand? Arm?]
4. The muscles are also distinguished, on the other hand, as the voluntary
and involuntary muscles, according as they are, or are not, under the
control of the will. The heart is an example of the involuntary variety. We
cannot change its action in the least by an effort of the will. When we
sleep, and the will ceases to act, the heart continues to beat without
cessation. The voluntary muscles, on the other hand, are such as are used
only when we wish or _will_ to use them--as the muscles of the hand or arm
(Fig. 9).
{27}
[Sidenote: 5. What are the tendons or sinews? Their strength? Color?
Location? Tendon of Achilles? The fable? Muscles of the leg?]
5. THE TENDONS.--Tendons, or sinews, are the extremities of muscles, and
are compactly fastened upon bone. They are very strong, and of a silvery
whiteness. They may be felt just beneath the skin, in certain parts of the
body, when the muscles are being used, as at the bend of the elbow or knee.
The largest tendon of the body is that which is inserted into the heel,
called the tendon of Achilles, after the hero of the Grecian poet, the
fable relating that it was at this point that he received his death-wound,
no other part of his body being vulnerable. The muscles which extend into
the leg unite to form a single and very powerful tendon, and enclose a
small bone called the knee-pan, which, acting like a pulley, greatly
increases their power, and at the same time protects the front of the
knee-joint (Fig. 10).
[Illustration: FIG. 10.--VIEW OF KNEE-JOINT. A, Thigh bone: B, Knee-pan: C,
D, Leg bones.]
[Sidenote: 6. Contraction of the muscles? Bending of the arm or finger?
Other agencies? Automatic movements? In cold-blooded animals?]
6. MUSCULAR CONTRACTION.--The muscles, when acted upon by the appropriate
stimulus, contract, or so change {28} their shape, that their extremities
are brought nearer together. The bending of the arm, or of a finger, is
effected in this manner, by the will; but the will is not the only means of
producing this effect. Electricity, a sharp blow over a muscle, and other
stimuli, also cause it. Contraction does not always cease with life. In
man, after death from cholera, automatic movements of hands and feet have
been observed, lasting not less than an hour. In certain cold-blooded
animals, as the turtle, contraction has been known to take place for
several days after the head has been cut off.
[Sidenote: 7. Contractility? Give the illustration. What was supposed? What
is the case?]
7. The property which, in muscle, enables these movements to take place is
called _contractility_. If we grasp a muscle while in exercise (for
example, the large muscle in the front of the arm), we notice the alternate
swelling and decrease of the muscle, as we move the forearm to and fro. It
was at one time supposed that the muscle actually increased in volume
during contraction. This, however, is not the case; for the muscle, while
gaining in thickness, loses in length in the same proportion; and thus, the
volume remains the same in action and at rest.
[Sidenote: 8. What further in relation to contraction? Weariness of a
muscle? Beating of the heart? Standing and walking?]
8. Contraction is not the permanent, or normal, state of a muscle. It
cannot long remain contracted, but after a shorter or longer time, it
wearies and is obliged to relax. After a short rest, it can then again
contract. It is for this reason that the heart can beat all through life,
night and day, by having, as we shall hereafter see, a brief interval of
rest between successive pulsations. For the same reason, it is more
fatiguing to stand for any great length of time in one position, than to be
walking the same period.
[Sidenote: 9. Muscular power of animals? How tested? Man's power? Horse's?
The comparison?]
9. RELATIVE STRENGTH OF ANIMALS.--The amount of muscular power which
different animals can exert, has {29} been tested by experiment. By
determining the number of pounds which an animal can drag upon a level
surface, and afterward comparing that with its own weight, we can judge of
its muscular force. It is found that man is able to drag a little less than
his own weight. A draught-horse can exert a force equal to about two-thirds
of his weight. The horse, therefore, though vastly heavier than man, is
relatively not so powerful.
[Sidenote: 10. Power of insects? Beetles? Give the conclusion.]
10. Insects are remarkable for their power of carrying objects larger and
heavier than themselves. Many of them can drag ten, and even twenty times
their weight. Some of the beetles have been known to move bodies more than
forty times their own weight. So far, therefore, from it being a fact that
animals have strength in proportion to their weight and bulk, the reverse
of that statement seems to be the law.
[Sidenote: 11. Difference in strength of individuals? How caused?]
11. PHYSICAL STRENGTH.--The difference in strength, as seen in different
individuals, is not due to any original difference in their muscles. Nature
gives essentially the same kind and amount of muscles to each person, and
the power of one, or the weakness of another, arises, in great part, from
the manner in which these organs are used or disused.
[Sidenote: 12. Complaint in relation to degeneracy? How true? How
determined by armor? The fair supposition?]
12. Many authors complain of the physical degeneracy of men at the present
day, as compared with past generations. There is room for doubt as to the
correctness of this statement. Certain experiments have recently been made
with the metallic armor worn seven hundred years ago, by which it is found
that any man, of ordinary height and muscular development, can carry the
armor and wield the weapons of an age supposed to be greatly our superior
in strength. When we consider that in those days, only very strong men
could endure the hardships of soldier-life, {30} it is fair to suppose that
our age has not so greatly degenerated in respect to physical strength.
[Sidenote: 13 Action? Use of organs? Training of the mind? The child's
brain? Education of the body?]
13. IMPORTANCE OF EXERCISE.--Action is the law of the living body. Every
organ demands use to preserve it in full vigor, and to obtain from it its
best services. The value of that training of the mind, which we call
education, is everywhere recognized. The child is early put to school, and
for many years continues to study, in order that his brain, which is the
great centre of mental power, may act healthfully and with force. It is
important that the body, also, should receive its education by exercise.
This is especially true of persons belonging to certain classes of society,
whose occupation confines them within doors, and requires chiefly
brain-work.
[Sidenote: 14 Work in the open air? A perfect business? The consequence of
universal perfect business? Occupation of children?]
14. Persons who are engaged in manual labor in the open air obtain all the
exercise necessary for bodily health in their regular business: their need
is more likely to be a discipline or exercise of the mind. A perfect
business of life, therefore, would be one which would combine both physical
and mental labor in their proper proportions. If such a business were
possible for all the human race, life would thereby be vastly prolonged.
Such is, in fact, to a large extent, the occupation pertaining to one
period of life--childhood. A part of the time is spent by the child in
improving his mind by study, and another part of the time he has physical
exercise in his games and sports.
[Sidenote: 15 In what does exercise consist? Effects of it?]
15. THE EFFECTS OF EXERCISE.--Exercise consists in a well-regulated use of
the voluntary muscular system. The effects, however, are not limited to the
parts used. Other organs, which are not under the control of the will, are
indirectly influenced by it. For instance, the heart beats more rapidly,
the skin acts more freely, and {31} becomes hotter, as well as the parts
beneath it, and the appetite and power of digestion are increased. An
increased exhalation from the lungs and skin purifies the current of the
circulation, and the body as a whole thrives under its influence.
[Sidenote: 16. General effect upon the muscles? Special effect? Effects of
inaction? Of excessive exercise?]
16. The immediate effect of exercise, however, is upon the muscles
themselves; for by use they become firm and large, and increase in power.
If we examine a muscle thus improved by exercise, we find that its fibres
have become larger and more closely blended together, that its color is of
a darker red, and that the supply of blood-vessels has increased. Without
exercise the muscle appears thin, flabby, and pale. On the other hand,
excessive exercise, without sufficient relaxation, produces in the muscle a
condition not very different from that which follows disuse. The muscle is
worn out faster than nature builds it up, and it becomes flabby, pale, and
weak.
[Sidenote: 17. Of violent and spasmodic efforts? Strength, how attained?
Give the particulars.]
17. Violent exercise is not beneficial; and spasmodic efforts to increase
the muscular strength are not calculated to secure such a result. Strength
is the result of a gradual growth, and is most surely acquired if the
exercise be carried to a point short of fatigue, and after an adequate
interval of rest. To gain the most beneficial results, the exercise should
be at regular hours, and during a regular period. The activity of the
exercise, and the time devoted to it must vary, of course, with the
strength of the individual, and should be carefully measured by it.
[Sidenote: 18. What may walking be called? What further is said of
walking?]
18. DIFFERENT MODES OF EXERCISE.--There are very few who have not the power
to walk. There is required for it no expensive apparatus, nor does it
demand a period of preliminary training. _Walking may be called the
universal exercise._ With certain foreign nations, the English {32}
especially, it is a very popular exercise, and is practised habitually by
almost every class of society; by the wealthy as well as by those who have
no carriages; by women as well as by men.
[Sidenote: 19. What is said of running, and other like movements? What, as
related to childhood? What instances are alluded to? Example?]
19. Running, leaping, and certain other more rapid and violent movements,
are the forms of exercise that are most enjoyed in childhood. For the
child, they are not too severe, but they may be so prolonged as to become
injurious. Instances have been recorded where sudden death has resulted
after violent playing, from overtaxing the heart: for example, we have the
case of a young girl who, while skipping the rope, and endeavoring to excel
her playmates by jumping the greatest number of times, fell dead from
rupture of the heart.
[Sidenote: 20. Carriage-riding? Horseback-riding?]
20. Carriage-riding, as a means of passive exercise, is particularly well
suited to invalids, and persons advanced in life. Horseback exercise brings
into use a greater number of muscles than any other one exercise, and with
it there is an exhilaration of feeling which refreshes the mind at the same
time. It is one of the manliest of exercises, but not less suitable for
women than for men. To be skilful in riding, it is best to begin its
practice in youth; but there are very few kinds of exercise of which the
same is not equally true.
[Sidenote: 21. Boating, swimming, and skating?]
21. For those who live near streams or bodies of water, there are the
delightful recreations of boating, swimming, and skating. Certain of these
exercises have a practical importance aside from and above their use in
increasing the physical vigor. This is especially true of boating and
swimming, since they are often the means of saving life. Practice in these
exercises also teaches self-reliance, courage, and presence of mind.
Persons who have become proficient in these vigorous exercises are
generally the ones, {33} who, in times of danger, are the quickest to act
and the most certain to do so with judgment.
[Sidenote: 22. What kind of exercise yields the best results? What advice
is given?]
22. PHYSICAL CULTURE.--That form of exercise which interests and excites
the mind, will yield the best results; but to some persons no kind of
exertion whatever is, at first, agreeable. They should, nevertheless, make
a trial of some exercise, in the expectation that, as they become
proficient in it, it will become more pleasant. In exercise, as many sets
of muscles should be employed as possible, open-air exercise being the
best. Parlor gymnastics, and the discipline of the gymnasium are desirable,
but they should not be the sole reliance for physical culture. No in-door
exercise, however excellent in itself, can fill the place of hearty and
vigorous activity in the open air.
[Sidenote: 23. Physical culture among the ancients? In Greece? In schools
and colleges at the present time? Result to the body and mind?]
23. GYMNASTIC EXERCISES FOR SCHOOLS AND COLLEGES.--In the system of
education among the ancients, physical culture predominated. In ancient
Greece, physical exercises in schools were prescribed and regulated by law,
and hence these schools were called _gymnasia_. At the present time, on the
contrary, this culture is almost wholly unknown, as a part of the course of
education, in our schools and colleges. In a few of our institutions of
learning, however, physical exercises have been introduced, with manifest
advantage to the students, and they form a part of the regular curriculum
of exercises,--as much so as the recitations in geography, grammar, or
Greek. The good effect of the experiments, as shown in improved scholarship
as well as increased bodily vigor, in the institutions where the plan has
been tried, will, it is hoped, lead to its universal adoption. We should
then hear less frequently of parents being obliged to withdraw their
children from school, because they become exhausted {34} or, perchance,
have lost their health from intense and protracted mental application.
[Sidenote: 24. The result of gymnastics in our colleges and other
institutions of learning?]
24. Were gymnastics more common in our educational institutions we should
not so often witness the sad spectacle of young men and women leaving our
colleges and seminaries, with finished educations it may be, but with
constitutions so impaired, that the life which should be devoted to the
accomplishment of noble purposes must be spent in search of health. Spinal
curvatures, which, according to the experience of physicians, are now
extremely frequent, especially among ladies, would give place to the steady
gait and erect carriage which God designed his human creatures should
maintain.
25. All the exercises necessary for the proper development of the body may
be obtained from the use of a few simple contrivances that every one can
have at home, at little cost--less by far than is spent for useless toys.
Many of these may be made available in the parlor or chamber, though all
exercises are far more useful in the open air. A small portion of the day
thus spent will afford agreeable recreation as well as useful exercise. The
Indian club, the wand, the ring, and the dumb-bells answer ordinary
purposes very well. Illustrations are here introduced of a few simple
contrivances that may be useful for general exercises, and are specially
suitable for persons with _weak spines_, or with spines that are the
subject of lateral curvature.
26. One of the simplest appliances for strengthening the muscles of the
spine, designed chiefly to exercise the muscles on either side of the
spine, consists of two wooden handles attached to india-rubber cords, one
of which is attached to a hook made fast in the ceiling, or in the top of
the door-case; and the other to another hook fastened in the wall,
door-post, or window-casing, about the height {35} of the shoulder. When
traction is made with the left hand, it exercises the muscles on the left
side of the spine, while those on the opposite side are left almost at
rest, owing to the oblique direction given to the shoulders when the right
hand grasps the horizontal cord. (This appliance will be understood by
referring to Fig. 13.)
[Illustration: FIG. 11.]
[Illustration: FIG. 12.]
{36}
27. Fig. 11 shows an appliance consisting of two strong elastic cords, with
handles, secured to a hook in the floor, so arranged that the patient has
to stoop forward to reach them. On raising the body the spinal muscles are
powerfully exercised. Fig. 12 shows other modes of using the elastic cords
for strengthening the spine and chest.
[Illustration: FIG. 13.]
28. These various appliances have been combined so as to form a system of
gymnastics suitable for parlor use; other appliances have been added by
which the muscles of {37} the legs may be called into action as well as
those of the spine and upper part of the body (Fig. 13). Combinations of
cords suitable for particular cases may also be made, and by using one or
several cords on the same hook, their power may be adapted to the strength
of the most robust as well as to that of the invalid, or of the most
delicate child. The entire apparatus is quite simple in its construction
and inexpensive, requiring but little space, and at the same time affording
a great variety of exercises.
EXERCISES THAT MAY BE PRACTISED ON THIS APPARATUS.
EXERCISE I. (Fig. 13).--Stand erect under the cords and place the heels
together. Grasp the handles firmly, keeping the knees and elbows stiff,
and pull downward and forward until the fingers nearly touch the toes.
Return slowly to the erect position. Repeat.
EXERCISE II. (Fig. 13).--Stand erect, and having grasped the handles
overhead firmly, separate them and bring them down slowly until they
touch the sides: then return them slowly to the original position.
Repeat.
EXERCISE III. (Fig. 13).--Stand erect, heels together, grasp the
handles overhead, and charge forward with the right foot. Return to
first position, and then charge with the left. Repeat, using the right
and left foot alternately.
EXERCISE IV. (Fig. 13).--Stand erect, heels together. Grasp the handle
overhead, and charge forward with the right foot, knee bent. Remain in
this position and bring the arms down to the sides so that the arm and
fore-arm may form a right angle. Still holding the handles, thrust
forward, first the right hand and then the left, until the arm is
straight. Repeat. Return to first position, then charge forward with
the left foot, performing the same movements as before.
EXERCISE V. (Fig. 13).--In this exercise we change to the pulleys
leading from the side posts, which can be used in several different
ways. 1st. Stand erect, heels together, facing one of the posts, grasp
the handle with the right hand, the arm being extended, then flex the
fore-arm on the arm. Repeat. Perform the same movements with the left
hand. 2d. Stand with back to the post; grasp the pulley behind with the
right hand, then gradually bring the hand forward until it is extended
in a straight line in front. Repeat. Perform the same exercise with the
left hand.
{38} EXERCISE VI. (Fig. 13).--This exercise is especially adapted to
the legs. Stirrups are so arranged that they can be attached to the
pulleys overhead, and can hang down to within three or four feet of the
floor. Place the foot in the stirrup, and then press down until it
touches the floor. Repeat. Exercise the left foot in the same way.
EXERCISE VII. (Fig. 13.)--This exercise requires a little attention in
the adjustment of the apparatus. Under the pulleys in the floor are
passed ropes which can be attached to the snap-hooks that hold the
handles overhead. Stoop forward with the knees stiff, and take hold of
the handles, and then raise the body to the erect position. Repeat.
EXERCISE VIII. (Fig. 13).--Sit on the floor or on a seat three or four
inches high; bend forward, take hold of the handles, and perform the
same movements that you would in rowing a boat.
EXERCISE IX. (Fig. 13).--The trapeze can now be let down; take hold of
it with both hands, sustaining the weight of the body with the arms,
then rotate the body first from right to left, then from left to right
alternately. This exercise is especially suitable for females.
EXERCISE X. (Fig. 13).--Grasp the trapeze as before, bearing all the
weight with the arms: then draw the body up slowly until you can place
the chin over the bars. This requires strength of muscle, and might
strain if done too violently; if slowly performed there is no danger.
These are but a few of the exercises that can be practised with this
apparatus. As these become familiar they can easily be modified, and
new ones can be arranged to meet the requirements of particular cases.
Most of the exercises described can be practised with one hand so as to
strengthen the muscles on one side.
[Sidenote: 29. Need of repose? How do we obtain rest? Alfred the Great? The
eight-hour division of time?]
29. REST.--We cannot always be active: repose must succeed labor. We obtain
this rest partly by suspending all exertion, as in sleep, and partly by a
change of employment. It is said that Alfred the Great recommended that
each day should be divided in the following manner: "Eight hours for work,
eight hours for recreation, and eight hours for sleep." This division of
time is as good as any that could now be made, if it be borne in mind that,
when the work is physical, the time of recreation should {39} be devoted to
the improvement of the mind; and when mental, we should then recreate by
means of physical exercise.
[Sidenote: 30. Cessation of voluntary activity? Temperature of the body?
Consequence? Body and mind during sleep? Nutrition? Describe it.
Consequences of insufficient sleep?]
30. During sleep, all voluntary activity ceases, the rapidity of the
circulation and breathing diminishes, and the temperature of the body falls
one or two degrees. In consequence, the body needs warmer coverings than
during the hours of wakefulness. During sleep, the body seems wholly at
rest, and the mind is also inactive, if we except those involuntary mental
wanderings which we call dreams. Nevertheless a very active and important
physical process is going on. Nutrition, or the nourishing of the tissues,
now takes place. While the body is in action, the process of pulling down
predominates, but in sleep, that of building up takes place more actively.
In this way we are refreshed each night, and prepared for the work and
pleasures of another day. If sleep is insufficient, the effects are seen in
the lassitude and weakness which follow. Wakefulness is very frequently the
forerunner of insanity, especially among those who perform excessive mental
labor.
[Sidenote: 31. Amount of sleep in different persons? Cases? Frederick the
Great? Bonaparte? Instances of long deprivation of sleep?]
31. All persons do not require the same amount of sleep, but the average of
men need from seven to nine hours. There are well-authenticated cases where
individuals have remained without sleep for many days without apparent
injury. Frederick the Great required only five hours of sleep daily.
Bonaparte could pass days with only a few hours of rest. But this long
continued absence of sleep is attended with danger. After loss of sleep for
a long period, in some instances, stupor has come on so profoundly, that
there has been no awaking.
[Sidenote: 32. Instances of sailors? French soldiers? During torture?]
32. There are instances related of sailors falling asleep {40} on the
gun-decks of their ships while in action. On the retreat from Moscow, the
French soldiers would fall asleep on the march, and could only be aroused
by the cry, "The Cossacks are coming!" Tortured persons are said to have
slept upon the rack in the intervals of their torture. In early life, while
engaged in a laborious country practice, the writer not unfrequently slept
soundly on horseback. These instances, and others, show the imperative
demand which nature makes for rest in sleep.
QUESTIONS FOR TOPICAL REVIEW.
PAGE
1. What can you state of the number and division of the muscles? 25, 26
2. Describe the structure of the muscles. 25, 26
3. Their arrangement in pairs and consequent action. 26
4. What is the difference between the motion called flexion and that
called extension? 26
5. Describe their action, and state which are the more powerful. 26
6. What is the difference between voluntary and involuntary muscles? 26
7. Illustrate the difference between the two. 26
8. State all you can of the tendons or sinews. 27
9. What is meant by contraction of the muscles? 27, 28
10. In how many and what ways may contraction be effected? 28
11. What is stated of after-death contraction? 28
12. Why cannot a muscle in life continue contracted a long time? 28
13. How then can the constant beating of the heart be explained? 28
14. How does the strength of a man compare with that of a horse? 29
15. What can you state in relation to the relative strength
of animals? 28, 29
16. What, in relation to physical strength? 29
17. What, in relation to physical degeneracy? 29, 30
18. What, in relation to the importance of exercise? 30
19. What is the effect of exercise upon the heart, skin,
and appetite? 30, 31
20. How does exercise affect the current of the body's circulation? 31
21. How does judicious exercise affect the muscles? 31
22. What is stated of violent and spasmodic exercise? 31
23. Of the exercise of walking? 31, 32, 33
24. Of running, leaping, and other modes of exercise? 32
25. Of physical culture, in connection with out-door exercises? 33
26. Of the importance of gymnastics in our schools and colleges? 33, 34
27. Of the importance of rest from labor or exercise? 38, 39
28. What processes take place during sleep? 39
29. What effects follow insufficient sleep? 39
* * * * *
{41}