alte 4. Repetition of evolutionary stages of the race. ae Primitive nervous system be. Primitive muscular system ec. Primitive circulatory system d. Later development of special organs. De The mature foetus. D. PRENATAL PERIOD The prenatal period extends from the moment of conception to the moment of birth. In considering the development of the new individual, remember that from the instant of conception the fertilized cell fuses with no other cell; it takes into itself no further living substance. It begins manufacturing its own protoplasm from the food substances it receives from the mother. The book of heredity for the individual is closed at conception. But the book of environment is just opening. | sara ae aa E. NATAL PERIOD During the 280 days of parasitic life the human foetus has carried forward its processes of nutrition, respiration (internal), excretion, and growth at the expense of the mother. hen comes the phenomenon of birth or separ- ation of the foetus and its appendages from the body of the mother. It is a hazardous and momentous change for this infant, when it suddenly is cast into the outer world to take up its independent existence. REFERENCES: *Kirkpatrick and Huettncr--Fundamentals of Health, Pp. 34-55, 411-450. Martin--Human Body, Pp. 592-613. , Conklin--Heredity and Environment, Chap. 1 Guyer--Being Well Born, Chap. 4 Dorsey--Why We Behave Like Human Beings, Chap. 1 MeMurrich, J.P.e--Development of the Human Body *Required reading. F. HEREDITY AND ENVIRONMENT - GROWIH AND DEVELOTMENT (the first determing force of Constructive Hygiene) From the moment of conception this new individual has been subject to two forces: Heredity or Nature, and Environment or Nurture. The great problem of development is the unraveling of the effects of these two and the assign- ment of its true value to cach. Through ages of speculation and scientific research these relationships have fascinated man and have given rise to an immense volume of investigation. 1. Environmentalist View Early thinkers believed that species might be transmuted by envi- ronmental changes and that life itself could arise from lifeless matter. Philosophers of the 17th and 18th centuries believed that man was the product wholly of environment. 2e Hereditarian View Modern biology has been responsible for the establishment of the vital importance of heredity both to the race and to the indivi- dual, It has failed to produce life artificially or to create Oe ~10- species oy means of experimental cvolutiona Neither heredity nor environment is all-inclusive. Both are ne- cessary for the highest form of development. Heredity is the first determining force in constructive hygiene. It may be defined as "the process which is responsible for the par- ticular comtinetion of transmissable characters possessed by an or- ganisme" (Burlingame) Methods of Study of Heredity Our knowledge of heredity has come to us by three principal methods: a» Observational. "Like produces like" came as a result of mankind comparing individuals, species, and races and observing certain constant resemblances and differences. bd. Statistical. This method studies characters singly and applies quantitative methods to them. Francis Galton was its founder. His researches were applied to several selected traits, as: Genius, artistic ability, stature, eye color, and certain di- seasese The two principles connected with the name of Galton are: (1) Law of Ancestral Inheritance: A statistical evaluation of the contribution of each ancestor to the individual. (2) Law of Filial Regression: Or tendency of children to return to the average of the group. The weakness of the method lies in the fact that it is not al- ways possitle by observation alone to distinguish between in- herited and environmental resemblances and differences. The statistical method outlined the problem of heredity; it did not solve it. c. Experimental (1) Mendel is the outstanding pioneer, with his study of the breeding of pease His experiments enabled him to formulate what are known as Mendel's Laws: Law of segregation Law of independent assortment The principles of Mendelian inheritance apply to man. Many inheritable traits, both normal and abnormal, have been shown to be of this nature. See the list given in Storey's Principles of Hygiene, Pp. 253-260. (2) Later research has confirmed and extended Mendel's observa- tions greatly. It has also added new conceptions which ex- plain some facts which were apparently inconsistent with his findings. The foremost of thesc newer principles are: -ll- (a) Linear order of genes (vb) Linkage of genes in chromosome (c) Crossing over of groups of genes (4d) Sex linkage of some traits Ge RACE BETTERMENT THROUGH CONSCIOUS CONTROL The growing problems of caring for the mentally and physically defective have led to a careful study of the causes of these conditions. Much defec- tiveness has been found to be directly or indirectly inheritable. As a re- sult of such studies a basis for improvement of the race, through the guid- ance of heredity, has been found. The application of our knowledge to this end is called Eugenics. It is the name given to a program for improvement of the human race by limiting the multiplication of inferior stocks and en- couraging the increase of superior ones. The problem has these two broad phases and it is proposed to approach its solution by two lines of attack. 1. Positive or Constructive Eugenics--measures to encourage reproduction of the best. a. Education regarding heredity be Selective mating ee Reproduction of superior strains 2. Negative or Restrictive Eugenics--measures to control the mating and re- production of the unfit. | a. Segregation or sterilization of defectives te Prevention of war c. Intelligent charity a. Safeguarding the quality of immigration oe Menaces to Racial Stock a. War be. Unwise charity ec. Undesirable immigration ad. Infertility of superior strains REFERENCES: *Storey~-Principles of Hygiene, Chap. 4 *Burlingame and Martin--General Biology, Chaps. 28-31 Carr=-Saunders--Eugenics *Conklin--Heredity and Environment, Chaps. 2-6 Gosney and Popenoe--Sterilization for Human Betterment Guyer--Being Well Born, Chaps. 1,2,6,7,8,13,15,23. Hutington and Whitney--The Builders of America, Chaps. 19-21 *Jennings--Biological Basis of Human Nature, Chaps. 6,8,10,15 Popenoe--The Child's Heredity Popenoe and Johnson--Applied Eugenics Stockard--Physical Basis of Personality *Kirkpatrick and Huettner--Fundamentals of Health, Chap. 3 *Required reading. ain IV. NUTRITION, the second determining force in Constructive Hygiene. "The growth of the human body, its weight, its physical and mental energy and vigor and its vital endurance are the results of the chemistry going on within and surrounding the human tissue cell."--Storey. The establishment of the cell-theory through the cumulative efforts of many investigators furnished a sound basis for understanding body processes, as well as solving many of the puzzles of heredity. As a basis for understanding the processes of nutrition by which the body provides for growth, maintenance, and repair, certain facts about the tissue cells should be remembered: Every tissue cell is a constructing and manufacturing chemical and physical la- boratory which is absolutely dependent upon the chemical supplies that are brought to it by blood and lymph streams. The chemicals proven necessary for normal functioning of the human tissue cells are: Carbon Phosphorus Calcium Hydrogen Sulphur Magnesium Oxygen Chlorine Tod ine Nitrogen Sodium Iron Potassium Copper Manganese Tissue cells are the “bricks” out of which every vart of the human body is built. These cells vary greatly in size, shape, and function. They are all composed essentially of the same basic material, protoplasm. From the chemical materials brought to them by the blood the huran tissue cells build, repair, or replace their own structure and manufacture their own special “functional ma- terial." The relation of the chemicals within the cell are both physical and chemical. The life of the cell is a continuous effort to reach static equilibrium. This is never reached during the life of the individual. A. CELL ENVIRONMENT AND HEALTH Health is dependent upon the chemical and physiochemical conditions within and surrounding the cells. These conditions are directly influenced by certain definite factors in the cell environment. Important factors in cell environment are: 1. Temperature 26 Water content Se Inorganic salts 4. Nutrients 5S. Vitamins 6. Hormones 7. Waste products 8. Reaction (Hydrogen in concentration) ibn An intelligent understanding of the relation of nutrition to health must be based upon a working knowledge of: 1. The physiology of the tissue cell. Re Se The character, composition and values of foodstuffs. The mechanisms of digestion and assimilation. 4. The hygiene of nutrition. De Some guides to adequate nutrition. Be PHYSIOLOGY OF THE TISSUE CELL All cells exhibit two types of functions, anabolic or constructive functions--performed chiefly by the nucleus; kataboliec or destructive functions--performed chiefly by the cytoplasm, Thus the nucleus of the cell is chiefly an organ of growth, construction, repair and reproduction while the cytoplasm is an organ of power production through energy transformation. Both of these functions are dependent upon the delivery to the cell of adequate nutritive materials and removal of the waste products. l. Metabolism: The sum total of the chemical activities occurring in liv- protoplasm. For purposes of study it may be further subdivided: Basal metabolism: The chemical reactions Which are concerned with the immediate maintenance of the living state. Growth metabolism: The whole group of reactions by which new proto- plasm is produced and new Supporting structure laid dow. Functional metabolism: Those reactions associated with the activi- ties of which protoplasm is capable, i.e., muscular, nervous, or : glandular, etc, C. THE CHARACTER, COMPOSITION, AND VALUE OF FOODSTUFFS. Le Foods - Composition and values Normal functioning of the cells of the body, which constitutes health, requires an adequate supply of the chemicals composing the human body. These chemicals are taken into the body in the food we eat, the water we drink, and the air we breathes The foods are needed for three main purposes: a. To secure energy. b. To build and repair tissue. cs» To regulate body processes. Sources; Soil and air are the ultimate sources of the chemicals required by the body. Plant life is the primary source of human food. Animal iafe te a secondary source. 5» Variety of Foodstuffs: Humans have found by centuries of experience and experiment that the needed chemicals can be secured from an atmost end- less variety of animal and vegetable sources. ain 4, Classification of Foods: Food compounds have been classified into groups according to their chemical composition and their physiological action. Most foods belong in more than one class, though usually they have one agominant function or value. 5. Food Groups: The food compounds and principles essential for human life may be classified into the following groups: a. Water e, Carbohydrates be Inorganic salts f. Oxygen c. Proteins g. Vitamins d. Fats h. Food accessories 6. Food Values: Our estimate of the value of various foodstuffs has been secured through three main standards of measurement: a. Chemical: For many centuries the sole wit of measurement was secured by chemical analyses. b. Physical: Values have been attached to foods, based upon their ability to produce heat, measured in heat units, Unit of measurement--Calorie (large) the amount of heat necessary to raise 1 kilogram of water 1° centigrade. c. Biological: The newer values are based upon carefully controlled feed- ing experiments on animals. 7. Minimum Essentials: While the exact chemical composition and physiologi- cal action of the numerous substances used for food would be useful and desirable, it is not necessary in order to intelligently sclect a well balanced dict to fit your peculiar needs. . The following facts, however, are considered the minimum essential know- ledge about each one of the food groups as guides to adequate nutrition: ae Function of group in body. b. Source from which it can be most cconomically secured physiologically . financially c. Nuantity required by body. d. Quality producing best results, (Note--Student is expected to look up the above facts about each one of the groups of foods enumerated above.) MECHANISMS OF DIGESTION AND ASSIMILATION 1. Preparation of Food To understand the varied aspects of the preparation of foods is one of the essential foundations of a nutrition program, This may be considered from the standpoint of its crude preparation by plants and animals; its refine- ment and distribution by man; and its physiological preparation by the body. ae Plant: Assembled by plants from the air and soil. : b. Animals: The making over of plant life into animal tissue. e. Production, transportation and distribution by man. d. Domestic: Preparation for consumption. €. Physiological preparation: digestion, «§5- £e Digestion The preparation of food for use by the body cells is called digestion. It is essentially a refining process, A useful conception may be ob- tained by considering the purposes of digestion: ae Mechanical: To break up the food into small particles. Accomplished by mastication and movements of stomach and intestines. be Physical: To dissolve or suspend particles in a semi-liquid. Accom- plished by secretions of alimentary system with assistance of hor- mones and secretogogueSe c. Chemical: To break up complex molecules of proteins, fats and carbo- hydrates and by recombination making them acceptable for assimilation by the body cellse This is accomplished through the various enzymes. Anatomy of Alimentary or Digestive System Alimentary canal is essentially a tube running through the body and lined by a vascular membrane, a large part of which is specially adapted for absorptione The tube is strengthened by muscular fibers, In the walls of the intestines are numerous glands, blood vessels,and lymphatics. Connected with alimentary tube are some larger glands whose function it is to pour the digestive juices into the canal. Subdivision of alimentary canal: (1) Mouth (4) Stomach (2) Pharynx or throat (5) Small intestines (3) Esophagus (6) Large intestines Glands - The large glands which form an essential part of the digestive system are: {1} Salivary glands (2) Liver {3) Panereas (Note: Student is expectcd to look up the anatomy and physiology of the digestive system. See references at end of Section on Nutrition.) Stages of Digestion a, Mouth Digestion: Or better a mixture of the food with secretions as preparation for salivary digestion. Importance of mastication. Saliva: Supplied by three pairs of glands: parotid, sublingual, and submaxillary. Character and amount. Content and action of enzyme, Ptyalin. Swallowing: A complex procedure involving a voluntary stage. Bolus of food is crowded back into the pharynx by the tongue where it is grasped by involuntary muscles and pressed on by peristalsis. b. Te Gastric Digestion The stomach is an important muscular organ guarded at its entrance and exit by sphincter muscles, It is not an empty cavity. It con- tracts around the food and goes through an orderly sequence of con- tractions and relaxations. These movements seem to further break up food and add to it the gastric secretions. When the digestive process has proceeded to a ¢ertain stage, the acid chyme causes pyloric sphincter to open and let out a small quantity of contents into the intestinese Gastric Secretions Character: Acid reaction (Hydrochloric acid) Amount: Three pints daily Secretions: (a) Psychic (bv) Secretogogues Enzymes; (a) Pepsin (bd) Rennin Intestinal Digestion Movements of Intestines: Peristalsis is slower and gentler than in the esophagus. Rhythmic motion moves food along in stages. Secretions: Bile, pancreatic juice; intestinal juice. The secretions of the intestines are alkaline in reaction. This ena- bles them to neutralize acids coming from the stomach, those due to bacterial fermentation of sugars, and those formed by fat digestion. Bile: A secretion of liver and temporarily stored in gall bladder. Action; (a) Stimulate splitting of fats by pancreatic juice. (ob) Enters into new formation of soans with fatty acids. {c) Promotes peristalsis. (a4) Helps to control bacteria. Pancreatic juice: Amount, i pint daily. Action, on all three forms of foodstuffs. Enzymes: Amylopsin; Trypsin; and Steapsin (or amylase, protease, lipase). Intestinal juice: Completes preparation of both proteins and car- bohydrates for acsorption. Enzymes: (a) Invertase) Maltase ) bring about final changes in sugars. lactase ) (b) Erepsin ) completes splitting of some pro- tcins into amino acids. Ke wl te é. Large Intestines As the food passes through lower part of small intestines and | beginning of large intestine water and absorbable materials are extracted from foods, at last leaving the waste products nearly solid and ready for discharge from the body. This is called the feces, and is made up of residue of diet (5%), excretions from the intestinal tract, and bacteria. Te Absorption of Foodstuffs The absorption of foodstuffs becomes the final and critical stage of digestion. The whole intestinal tract has some powers of absorption. The most important part is the small intestines. (1) Mechanism of Absorption The intestines are so arranged that the liquid or semi-liquid foodstuffs can come into intimate contact with as large a surface of intestines as possible, This is accomplished through the villi of the intestinal wall. (2) Process of Absorption (a) Osmosis and dialysis (bo) Action of epithelial cells (3) Routes of Absorption (a) Blood stream through capillaries of villi into general blood stream. (b) Lacteals to the lymphatic system through the thoracic duct to blood stream. (4) Form of Absorption of Foodstuffs (a) Carbohydrates absorbed mostly as simple sugars. (bo) Fats are split into fatty acids and glycerin. (c) Proteins are split into amino acids. HYGIENE OF NUTRITION While a knowledge of the digestive system and a familiarity with the food composition and values is important, the factors included under the term “hygiene of nutrition" are of equal importance. The levels of nutrition are markedly influenced by the following factors: 1. Be Environment. The environment in which food is taken may help or hinder its digestion. (a) Character of service - cleanliness, etc. (ob) Preparation of food - appearance, taste, odor. Emotional state: It has been proven that in both man and animals the emotions have a direct bearing upon the secretion of the digestive juices. (See Cannon: Bodily Changes in Pain, Fear, etc, - on Reserve Shelf). 36 4e De 6. 79 -1e- Physical State: Fatigue, either acute or chronic, may be a determining factor in successful digestion. Mastication: Thorough mastication of food is the first step in normal digestion, This requires normal teeth and proper habits of eating. Rate of Eating: The gulping of partially masticated food is one of our most serious errors in the hygiene of nutrition. Why? Amount and Character of Food: The selection of the proper amount and balance of foods for the individual is of vital importance. Guide to Successful Nutrition: In attempting to judge whether his nutri- tion is normal, the individual can take certain factors as guides: a, Hunger: A general term by which we express the demands of the body for food to replace waste, supply energy and building materials. Sensation is referred to stomach. Taken alone it is not a safe guide, be Appetite: Is psychic as well as physical. It expresses both a desire for and a relish of food. ce Height and weight tables The height and weight tables graduated for age are one of our practical indices of nutrition. The "average" weights shown on these tables are not an absolute criterion. Due allowances must be made for race and family habit. For children the Sydenstrick er and the Baldwin-Wood tables are best; for adults, the Insure ance Company Tables. Life insurance experience suggests that the optimum weight for young adults (under 40 years of age) is 5810% above the average weights of tables. ad, Objective signs of successful nutrition These are important guides for individual: (1) Color of skin and lips (2) Firmness of muscles (3) Posture (4) Regularity of excretions e, Subjective signs of successful nutrition (1) Foeling of well-being (2) Energy (3) Endurance (4) Prompt recovery from fatigue =IDe f. Diet Assurance of a balanced, adequate diet should be based upon actual body needs as adapted for age, weight, and intensity of activities. This may be estimated for practical purposes by the following scale: (1) Energy values Light exercise: 40-50 calories ) Vigorous exercise: 45-50 calories ) per kilogram of body weight Very severe exercise: 50-60 calories) (2) Balance The total calories needed for each day should be distributed among the food groups approximately as follows: Protcin calories: 10-12% Fat calorics: 35% plus Vitamins Carbohydrates calories: 55% (3) Choice of Diet: The following outline may be used as a guide to selection of a well-balanced food intake, Each day's diet should contain the following: Meat or fish, once daily. Adult, 1 pint of milk. Two servings of fruit--one fresh whenever possible. Two vegetables, one leafy and one root. Potatoes. Butter (at least 2 pats). Egg, alone or in combination. Whole grain or cereal. (4) Diet Project: The application of these facts should be made by the student in the Diet Project which forms an essential part of the course. REQUIRED READING: Storey--Principles of Hygicne, Book 1, Chap. 5, Discussion of Principlcs Martin--Human Body, Chap. 26, Anatomy of Digestive System Hough and Scdgwick--Thce Human Mechanism, Chaps. 8-13-19, Digcstion and Nutrition Kirkpatrick and Huettner--Fundamentals of Health, Chaps. 4 and 5 Meredith--Hygiene, Chape 3, Hygicne of Eating Williams--Personal Hygicne Applied, Chap. 7, Hygiene of Nutrition Ros¢--Feeding the Family, Chaps. 1, 2, and 10. COLLATERAL REFERENCES: Martin--Human Rody, Chaps. 25, 27 to 30 inc. Bogert--Nutrition and Physical Fitness, Chaps. 1-14. ~20- Meredith--Hygiene, Chaps. 32 and 34. Sansum--The Normal Diet. Cannon--Bodily Changes in Hunger, Fear Sherman--Chemistry of Food and Nutrition MeCollum Simonds--The Newer Knowledge of Nutrition Eddy--Mutrition Emmerson--Diagnosis of Health V. EXCRETION, the third determining force in Constructive Hygiene The objective of the processes of excretion is to neutralize, dilute, and _rgmove promptly and effectively the products of digestion snd. cell activities. Excretion may be described as the chemical results of cell activities. These products are produced by: Wear and tear on living structures of cells. Residue from manufacture of cell products. Death of cells. (a) (b) (c) Wastes due to oxidation within cells. (a) (e) Waste products from foods. Elimination is the series of processes by which the excretions are prepared and transported out of the body. A. TYPES OF EXCRETIONS 1. Internal: é- External: Those excretions which are discharged directly by the cell into lymph or blood stream, Those excretions discharged by cells upon surfaces that com- municate with the outside of the body. Be ORGANS OF EXCRETION 1. Kidneys: The most important organs of the body which are developed particularly for purposes of excretion. a. Description: The kidneys are two organs situated on cither Ce side of the front of the spinal column in the region of the floating ribs behind the stomach, pancreas, and liver. They arc oval or bean-shaped, abeut 4 or 5 inches long, and 1-5 inehes thick. Color: They are dark in color on account of the large blood supply. Structure macroscopically: The kidneys are observed to be covered with resistant capsule. On the side toward the spinal colum is a depression (hilum) through which vessels, ducts, and nerves enter and leave. Inside of this dep. ssion is an open space called the pelvis of the kidney. a Microscopically: The kidneys have two layers, cortex and medulla, The cortex or outer layer is a special arrangement of tissue cells and tubules in a way to make possible the free passage of larger quantities of blood in intimate con- tact with the special cclls and tubules. d. -2)]- Function: As the blood passes through the kidneys, the waste pro- ducts are extracted in two ways: (1) Mechanical filtration (2) Selective action of cells The urine thus excreted is gathered by series of tubules and emptied into the duct (ureter) of the kidney and is carried to the bladder. e. Mechanism of excretion: The extreting unit of the kidney is made up Be of a microscopic collecting tubule connected with a tuft of capil- laries. Significant structural features (1) Arrangement of capillaries to secure higher capillary pressure than elsewhere in the body. (2) Exceptional thinness of membrane. (3) Cells capable of secretory function. Significant function features (1) Mechanical filtration. (2) Re-absorption and secretion in tubules. Amount of excretion: The amount of urine varies considerably under normal circumstances, Average amount 3 pints (1200 - 1500 ce or 40-50 ounces). Amounts less than 500 ce (1 pt.) or more than 3000 ce (3 ats.) if persistent should be considered as a departure from normal. i. Composition: Color - yellowish or amrer 2. Lungs organ ae Reaction - acid Sp. Gravity - 1015 - 1025 Water - 96-97% Solids - 4-3% -- Urea, ereatinin, uric acid, inorganic salts. are an important excretory organ, heat regulatory apparatus, and an of nutrition. Area: Inner surface total area 90 sq, meters or 100 times as large as the total area of the skin surface. This inner surface of the lungs is in direct contact with the air in the spaces (alvcoli) of the lungs. Thc mombranous walls contain the blood vessels that bring blood from the heart. The entire blood supply is spread out in the pulmonary capillaries every fow minutes. . bs Lung capacity ) Residual air 1000 ce after cxtreme expiratory effects. ) Tidal air 500 ce ordinary quiet inspiration. ) Complemental air 1600 ce deep inspiration. ) Supplemental air 1600 ce deep expiration | Total capacity 4700 ce (1 (2 (3 (4 Vital capacity = Tidal plus complemental plus supplemental air. ~BPw Ce Lung functions (1) Absorption of oxygen (2) Removal of carbon dioxide (3) Heat regulation Se Skin is secondarily an organ of excretion. Some of its other functions are: ae Protection of body structures b. Sensory surface e. Regulation of body temperature Excretory function of skin is carried on by (a) sweat glands; (b>) sebaceous glands. ae Sweat glands: Over entire surface of body. Simple tubular glands coiled at the end, Amount of secretion varies with: {a) condition of atmosphere; (b) physical and psychical status. Usually acid in reaction contains urea, uric acid, creatinin, and sulphates. Inereased by: (a) Muscular activity (b) Heat (ce) Emotion (a) Drugs Decreased by: (a) Lower temperature (b) Emotion be. Sebaceous glands: Simple glands all over surface of skin, usually associated with hairs. Secretion (sebum) an oily semi-liquid mater- ial. Contains: fats, soaps, cholesterin, cell debris, and inorganic salts. 4, Intestines are important organs of excretion as well as of nutrition. They carry off the useless remains of diet and also the waste products from cell physiology. The somi-liguid chyme is passed along intestines by peristaltic action. As it progresses through the small’ intestines the portions acceptable to the body cells are absorbed into the blood lymph streams. When the larg intestine (colon) is reached the movements favor free absorption of water leaving behind a pasty mass called feces. Defecation is partly volitional and partly automatic due to stimuli arising from distention of the rectum. Defecation occurs by the voli- tional opening of the muscular sphincters controlling the anus. Bin C, HYGIENE OF EXCRETION 1. Kidneys: Susceptible to overstrain but are wonderfully effective mechanisms if given reasonable treatment. Protections: (a) Ample water (b) Adequate diet (c) Exercise (d) Proper posture (e) Periodic health examination &e Intestinal: The regularity and effectiveness of excretions by the bowels is influenced by: (a) Lack of proper habits of evacuation (b) Unsuitable diet (c) Weak abdominal muscles (d) Too little exercise (e) Low fluid intake 5. Lungs: Air necds of the body in character and amount. (a) Effective ventilation (b) Proper breathing 4. Skin: -Its function and appearance are guides to successful nutrition. Its effectiveness as an excretory organ is influenced by: (a) Digestion--quality and quantity of diet (b) Cleanliness-=bathing habits REQUIRED READING Storey~-Principles of Hygiene, Book l, Chape 6 Martin--Human Body, Chap. 31 Kirkpatrick & Huettner--Fundamentals of Health, Chap. 9 Meredith=-Hygiene, Chap. 35 Williams~-Personal Hygiene Applied, Chap. 10 COLLATERAL REFERENCES Burton-Opitz--Textbook of Physiology, Section on Excretion Stiles--Nutritional Physiology, Chap. 17 or VI. EXERCISE, the fourth determining force in Constructive Hygiene A. B. BRIEF DISCUSSION OF THE ANATOMY AND PHYSIOLOGY OF THE NEURO-MUSCULAR (MENTI*MOTOR) MECHANISM, 1. Re The Muscular System: Evolution of the system; relation to evolution of other systems and to development and conditioning of these systems. Forms 41% (+) of total body weight; most active of tissue cells in demand for nutrients and in transforming potential into kinetic energy; muscle activity produces most profound changes in environment of all tissue cells; some of the general effects of muscular activity on the muscles and on other systems: e.g., circulatory; respiratory; alimentary or digestive; excretory; heat regulatory; nervous. Kinds of Muscle Tissue Cells, and where found in body. a. Skeletal, Striated, or Voluntary Muscle. Location: Attachment to bones; fasciae; tendons, structure of the voluntary muscle cell; sarcolemma fibrils; sarcoplasm; blood supply; connection with nervous system; sensory and motor nerve endings in muscles, Functions of Skeletal Muscles: Connection with motion and locomotion; relation to posture; production of body temperature; storage and oxidation of glycogen; production of lactic acid and CO» during activity; relation to respiratory movements and to certain excretory functions. b. Smooth, or Involuntary Muscles Found in walls of alimentary canal; walls of blood vessels, bladder; ducts from glands, uterus, etc.; structure and characteristics; effects of voluntary muscular activity on these structures, ¢, Cardiac, or Heart Muscle LTS ER Structure and characteristics of the cells; compare with cells of smooth and striated muscle; characteristic of rhythmic contractabili- ty; control of rate through nervous system; chemical factors which influence rhythm; "all or none" theory of contraction. THE NERVOUS SYSTEM Anatomical and physiological considerations. i. Re The great coordinator of all bodily activities; relation to neuro- muscular (menti moter) mechanism: one unified system, but divided for purposes of discussion and understanding; the neurons, or nerve-tissue cells; characteristic forms of these cells; specialized to receive, transform, cr transmit stimuli, affector, effector, and association neurons within the system. Main Divisions of the Nervous System a. Central (or Cerebro-Spinal) includes cerebrum, cerebellum, medulla, and spinal cord, ~25- b. Peripheral nervous system includes nerve trunks which leave or enter central system. The twelve pairs of cranial nerves, their general distribution and function; the thirty-one pairmof spinal nerves, their general distribution; the thirty-one pairs of spinal (sensory) ganglia; meaning of afferent (receptor) and efferent (effector) neuronis; association neuronis, etc, ¢. Autonomic or Sympathetic nervous system. The ganglia; general distribution and functions of this part of nervous mechanism; connection with the central system; functions controlled by this division of nervous system. C. EFFECTS OF MUSCULAR ACTIVITY (exercise) upon: 1. Se The Muscle Cell, and muscular system. (Refer back to earlier discussion). Its nutrition, size, production and elimination of wastes, endurance, nerve control developed through voluntarv muscular exercise; immediate and remote (or ultimate) effects of exercise upon the various systems. The Nervous Mechanism Integratian through exercise; how this is brought about. (Refer to dis- cussion of nervous system above). Circulatory Mechanism Effect of sitting, standing, running in place on heart rate; on systolic, diastolic, and pulse pressures; effects of exercise of speed, of effort, and of endurance on these pressures; exercise as the chief means of strengthening and conditioning this mechanism; athletics and longevity; ("Do athletes die young?"); dangers from inadequate exercise; stenderd tests of cardiac efficiency; importance of physician's examination and advice if heart is abnormal in function or structure; local and general infections in relation to exercise and care of the heart; hygiene of exercise in relation to care of circulatory mechanism. Respiratory Activity and the Respiratory Mechanism a. The Normal Respiratory Rate: Before and during exercise of varying intensity and duration; effects of exercise on rate and denth of respiratory movements. b. The chemical changes produced as represented in Op intake and COs output. ¢. The Respiratory Mechanism: Location of lungs; size; shape, aerating surface; ventilation of; vital capacity and exercise, (See back un- der nutrition and excretion for meaning of tidal, supplemental, com- plemental, and residual air). Exercise and respiratory efficiency; how muscular exercise develops and conditions this mechanism. ~26- D. THE HYGIENE OF EXERCISE -- SUMMARY l. Muscular activity does more than develop muscular strength, skill and endurance. It is the fundamental developer of all the organic systems and functions of the body: circulatory, respiratory, excretory, heat regulatory, nervous, menti moter, and even skeletal structures. Muscular action begins in the nervous system its influence on nutritive and all other functions relating to a healthy body. Fxercise should be adanted to: age, sex, strength, and vitality of the individual; to occupation, and to climatic conditions. Qo Ce For Children: Pley is best; play is the "driving urge” in childhood to insize organic development; a healthful environment and opvortunity for whoicsome vlay life should be meintained through social organi- zaticn and leadership to secure normal physical, mental, and social health. Evidence of recognition of above in playgrounds since 1906, and in required physical education movements since 1916. For Adolescents: A period of rapid growth and stormy mental life; needs and capacities at this stage of life should be reckoned with in the organization and leadership in activitics at this period; big muscle-social activities represented by team games; athletics and rhythmic activities are best for this age; dangers where adolescents are stimulated by wrong standard of competition; high school and college programs of physical education; their organization and administration. For Adults: Exercise should be enjoyable, moderate, satisfying; participated in primarily for recreation and conditioning values; variability in intensity and duration reouired to satisfy organic and other needs at ages from 25 to 50 years of age; types of activity suitable for different age levels. For Later Years; Activity level should be lower; changes in organism which must be taken into account; deterioration of tissues; lessened elasticity of arterial walls etc. These changes are often hastened by unfavorable ways of living; types of activity for these age levels; golf, walking, gerdening, horseback riding, etc. Occupation: Sedentary occupations reouire definite planning for regular exercise; should be recreative and not too strenuous to maintsin henlth; strenuous muscular occupations should be reflected in types of recreative activities selected by the individual; discrim- inating judgements essential; organizations and movements which attempt to meet these needs. Other hygienic considerations in the regulation of exercise: (1) Fatigue: Causes; effects of habituation to exercise; normal fatigue; chronic fatigue. (2) “tuscular soreness: Theories as to cause. (3) The heart and athletics: Importance of being "in condition" for competition in games; focal, and general infections in relation to exercise; periodic health examination in control of individual, school, and other programs of physical edu- cation. Evidence pro and con. (4) Exercise in relation to posture, "personality," nervous stability; applications of exercise as a corrective, remedial, or therapeutic agent. (5) Summary. REFERENCES : *Storey, T.eA,--Principles of Hygiene (1930) pp 152-160 , “Martin, HeN. and E.G.e--The Human Body, llth Edition, pp 101-176 including chapter on nervous system. Williams, J»eF.--Athletics in’ Education (1930) pp 66-115 *Williams, J,F.--Personal Hygiene Applied, 2nd Edition, pp 111-130 Martin, HeG. and Weymouth, F.W.--Elements of Physiology, pp 78-133, including section on nervous system. Meredith, F,L.--Hygiene (1926) pp 92-118 Cowdry, EZ. V.--Human Biology and Social Welfare *Hough, Sedgwick and Waddell--The Human Mechanism, Revised Edition, (1918) pp. 297-326 Bainbridge, F. A.--The Physiology of Muscular Exercise (1919), pp 1-22, 171-201 MeCurdy , J+He and McKenzie,R.T.--Physiology of Exercise, pp 45-71, -68-110, 189-221 *Kirkpatrick and Huettner--Fundamentals of Health (1931) Chaps. 6 and 7, DD. 190-273, part of Chap. 10, pp 341-354. *Reauired VII-e PLAY, the fifth determining force in Constructive Hygiene A. INTRODUCTION : "Play is a basic activity requisite for the acquisition and conserva- tion of mental and physical growth and health."--Storey Play may be said to be innate tendency (an “impulse,” and 'urge," a "drive") to activity, the purpose of which is development and education leading to adult adjustment to social and material environment; play is activity in which the whole personality is enlisted; chief business of childhood is play. Through play, the child's menti motor, organic, impulsive (or emotional), and interpretative (or intellectual) mechan- isms are developed, strengthened, and integrated, This is why play isa "basic activity." Above consideration has been given to various bodily systems and their functions as if cach were an entity. Human life and health are products of the harmonious working together, or integration, of all of these systems and all of their activities brought about through — the nervous system. The gel general structures and functions of the nervous system were ~28~- discussed above ina section of the chapter on Exercise, The. stuient is referred to’ this discussion for details of anatomy and physiology of this system.. A consideration of play involves problems related to the devel- opment , thc integration, and the conditioning of the nervous system which have a connection with our concepts of "mind." Breause this is so, this part of the discussion will. involve considcrations of the relationships of play to mental health and mental hygiene. Be FORMS OF MIND Stages in the evolution of "mind" may be indicated by certain terms used in our text (and other writings) as they relate to types of behaviar at cértain stages ‘of development in the individual or in his tissue cells. ‘These terms are: il. "Tropic mind" -~- mind of cells (germ cells, etcs) 2, "Reflex ind" -- mind of embryo (Storey) 3. “Unconscious or subconscious mind" -- inherited mental experiences (nerve patterns, etc.), perhaps early mental stimuli not gaining conscious expression. 4. Adult, or Conscious “Mind: While the conscious mind beins to be evident in. cariy stages of infancy and childhood, its adult form is reached in later adolescence, or early maturity. It is a product of the grajual development of psychic traits resulting from stimuli brought into the nervous: system from .the environment (or from other organs of the body) and from the responses made to these stimuli. It is now believed that play. is exceedingly important not only in the development of. "mind" but as a factor in the hygiene of the mind (or mental hygiene). .,There are aspects of this problem which are of vital importance: @eg., relation to the social organization of the play life of ‘children and adults, and in relation to certain abnormal or pathological conditions which may arise. C,. PLAY AND THE MIND 1.