Part 12 (1/2)

177. _Relaxation must follow contraction, or, in other words, rest must follow exercise._ The necessity of relaxation, when a muscle has been called into action, is seen in the example of a boy extending his arm with a book in his hand, as a penalty. The boy can keep the arm extended but a short time, make what effort he may. It is also seen in the restlessness and feverish excitement that are evinced by persons gazing on troops during days of review. The same is noted in shopping.

Such employments call into action the muscles that support the spinal column in an erect position, and the languor or uneasiness is muscular pain. The long-continued tension of a muscle enfeebles its action, and eventually destroys its contractility.

178. _In school, the small children, after sitting a short time, become restless._ If their position be changed, their imperfectly developed muscles will acquire tone, and will again support the spinal column erect without pain. The necessity for frequent recesses in school, is founded on the organic law of muscular action alternating with rest. The younger and feebler pupils are, the greater the necessity for frequent recesses. We would not have the teacher think that one half of the time should be spent in recesses; or the mother, that her daughter is going to school to play. But we do maintain that recesses should be given, and that they should be short and frequent, especially for small and feeble scholars.

179. _Exhaustion is the inevitable result of continued muscular contraction._ For example, let a lady ply the needle quickly for some hours, and the muscles of the back and right arm will become exhausted, which will be indicated by a sense of weariness in these parts. A change of employment and position calls into action a different set of muscles, and the exhausted organs are relieved.

177. What is said of the contraction and relaxation of the muscles?

Give examples of the necessity of relaxing the muscles. 178. Why should not small children be confined in one position for a long time?

What evils result from this practice? What cla.s.s of pupils should have recesses most frequently? 179. What effect has continued muscular contraction?

180. _Much more labor will be accomplished by taking time to relax the exhausted muscles_, or by so changing the employment as to bring into action a new set of muscles; the woodman thus relieves himself, by sawing and splitting alternately. This principle applies to the labor of the horse and ox; and it is also applicable to all kinds of employment. With the invalid convalescing from fever, relapses result from inattention to these laws. When a patient is recovering from sickness, his physician should take care that his exercise be proper, neither too much, too little, nor too long continued.

181. _The muscles of growing youths will not endure so much exercise or labor as those of mature men._ In youth a portion of the vital, or nervous energy of the system, is expended upon the growth of the organs of the body, while in the individual who has attained his growth, this expenditure is not demanded; consequently severe labor or exercise should not be imposed on growing children.

_Observation._ In the campaigns of Napoleon Bonaparte, his army was frequently recruited by mere boys. He complained to the French government, because he was not supplied with men of mature years, as the youths could not endure the exertion of his forced marches.

182. _The muscles should be gradually called into action._ These organs in action require more blood and nervous fluid than when at rest. As the circulation of these fluids can only be increased in a gradual manner, it follows, that, when the muscular system has been in a state of rest, it should not suddenly be called into vigorous action. On arising from a bed, lounge, or chair, the first movements of the limbs should be slow, and then gradually increased.

_Observation._ if a man has a certain amount of work to perform in nine hours, and his muscles have been in a state of rest, he will do it with less fatigue by performing half the amount of the labor in five hours, and the remainder in four hours. The same principle should be regarded in driving horses and other beasts of burden.

180. How can the greatest amount of labor be secured with the least exhaustion to the muscles? 181. Why should not severe labor be imposed on growing children? 182. How should the muscles be called into action?

183. _The muscles should be rested gradually, when they have been vigorously used._ If a person has been making great muscular exertion in cutting wood, or any other employment, instead of sitting down to rest, he should continue muscular action, for a short time, by some moderate labor or amus.e.m.e.nt.

184. _If the system has been heated by muscular action, and the skin is covered with perspiration, avoid sitting down_ ”to cool” in a current of air; rather, put on more clothing, and continue to exercise moderately. In instances when severe action of the muscles has been endured, bathing and rubbing the skin of the limbs and joints that have been used, are of much importance. The laboring agriculturist and industrious mechanic, by reducing to practice this suggestion, would thus prevent soreness of the muscles, and stiffness of the joints.

185. _The muscles should be abundantly supplied with pure blood._ This state of the circulating fluid requires a healthy condition of the digestive apparatus, and that the skin should be kept warm by proper clothing, clean by bathing, and be acted upon by pure air and good light; the movements of the ribs and diaphragm should be unrestricted, and the lungs should have ample volume and be supplied with pure air.

In all instances, muscular power is greatest when the preceding conditions exist, as the muscles are then stimulated by pure blood; consequently, it is of practical importance to the mechanic, the farmer, the man of leisure, and not less so to the ladies, to observe these conditions, whatever vocation of life they pursue.

183. How should the muscles be rested when they have been vigorously used? 184. What precaution is given when the skin is covered with perspiration? How may soreness of the muscles, consequent upon severe action, be prevented? 185. Should the muscles be supplied with pure blood? When is muscular power the greatest?

186. _The muscles should be used in pure air._ The purer the air we breathe, the more stimulating the blood supplied to the muscles, and the longer they can be used in labor, walking, or sitting, without fatigue and injury; hence the benefit derived in thoroughly ventilating all inhabited rooms. For the same reason, if the air of the sick-room is pure, the patient will sit up longer than when the air is impure.

_Observation._ It is a common remark that sick persons will sit up longer when riding in a carriage, than in an easy chair in the room where they have lain sick. In the one instance, they breathe pure air; in the other, usually, a confined, impure air.

187. _The muscles should be exercised in the light._ Light, particularly that of the sun, exercises more or less influence on man and the inferior animals as well as on plants. Both require the stimulus of this agent. Shops occupied by mechanics, kitchens, and sitting-rooms, should be well lighted, and situated on the sunny side of the house. Cellar kitchens and underground shops should be avoided.