It should be remembered that an overweight child cannot be classified as a well-developed child. Even with an increase in body weight by 15-20%, children’s performance decreases, irritability increases, and musculoskeletal disorders may occur.
It should be taken into account that during before school age weight accumulation and growth increase fluctuate - in some periods the baby stretches upward faster, and in others he gains weight faster. So, usually in the years from four to six, the increase in the baby’s height is more noticeable (up to 15 cm in two years) than the increase in weight (up to 5 kg); therefore, sometimes it seems that the child is losing weight. Meanwhile, it is during these years that a noticeable accumulation of muscle strength begins, endurance increases, and mobility increases.
To ensure the normal physical development of the child, give him the necessary load on physical activities It is necessary to take into account the anatomical features, as well as the functional capabilities of the child’s body. The characteristics of children’s movements and their coordination capabilities change significantly from age to age, which significantly affects the organization of classes. physical culture.
The muscular system in children is formed on the basis of the development of the nervous system and an increase in the mass of skeletal muscles, and this process occurs unevenly. At an early age, the child’s bones are rich in blood vessels and contain a small amount of salts They are elastic, flexible, easily deformed and bent, as skeletal system 2-3 year old children have significant areas of cartilage tissue, weak, soft joints and ligaments. Children do not yet have stable curves in the spine, which appear only by the age of 4. All this must be taken into account when conducting physical education classes. For example, if the exercise is performed lying on the back, it is necessary for the child to lie straight. Strength exercises (carrying weights, hanging on hands, etc.) and those associated with long passive waiting are excluded.
It is recommended to pay special attention to the development of the arch of the foot, since in the second and partially in the third year of life it is flattened. Therefore, it is useful to train children in lifting, walking on their toes, walking on an inclined plane and on a ribbed board.
Small children breathe shallowly, often, unevenly, since the respiratory muscles are not yet fully formed. The development of a child’s body mastering walking leads to a restructuring of the breathing process and the gradual strengthening of the corresponding organs. The frequency normalizes, a thoraco-abdominal and then a thoracic type of breathing appears, and the lung capacity increases. Breathing increases only with excitement or physical exertion. Considering the characteristics of the respiratory system of preschoolers, care should be taken to ensure that they are exposed to as much as possible fresh air.
Prolonged physical and mental stress can negatively affect the activity of the heart and lead to disturbances in its function. Therefore, you should be very careful in dosing physical activity on the child’s body. The work of the heart is closely related to muscle development. Regular exercise trains the heart muscle and leads to a gradual decrease in heart rate.
If the baby experiences positive emotions, this activates him and promotes the normal functioning of the cardiovascular and nervous systems. The content of the exercises should captivate and interest the child. You should not force him to study - coercion causes a natural protest and gives rise to negative emotions.
Properly done work on the development of movements has a positive effect on the activation of vision and hearing.
Age characteristics of the child’s body
When planning classes, you should definitely take into account the age-related characteristics of the child’s body, since over the course of 2-7 years they are very changeable.
Children aged two to four years go through a difficult journey of acquiring vital skills, abilities and habits.
Two-year-old children begin to master jumping. At first, these are rhythmic half-squats with an attempt to slightly lift the feet off the floor, then jumping in place, jumping from a small elevation, jumping over an object and over a short distance. In three-year-old children, the push-off when jumping becomes energetic, they can regulate the force of the push.
In the third year of a child’s life, the development of his movements prevails over the development of other functions. Kids master all basic movements. Walking improves, the length of successive steps begins to equalize, and the direction of movement becomes straighter. At this age, children are attracted to complicated walking: with overcoming obstacles in the form of a slide, a ladder, a combined bridge on which you can go up and down, with stepping over objects and grooves. Kids love to carry objects, performing simple actions with them on the go. Kids successfully climb vertical ladders, love to press the bicycle pedals, and enjoy playing with a ball.
By the fourth year of life, the anatomical maturation of the child’s entire motor system is completed. A four-year-old child runs easily and jumps on one leg. He has a well-developed mechanism for coordinating various movements and maintaining balance.
By the age of five, muscle mass increases significantly, especially in the lower extremities, and muscle strength and performance increase. However, children are not yet capable of significant muscle tension and prolonged physical activity.
By the age of six to seven years, the formation of the tissue of the lungs and respiratory tract is largely completed. However, the development of the respiratory organs at this age is not yet completely completed: the nasal passages, trachea and bronchi are relatively narrow, which makes it difficult for air to enter the lungs, the chest and ribs cannot fall as low as in an adult when inhaling. Therefore, children cannot take deep breaths and breathe faster than adults.
Caring for physical education should begin with creating a favorable emotional microclimate, ensuring a clearly established daily routine, proper nutrition, systematic hardening, widespread use of physical exercises in children's lives.
Section II. Conditions normal development and promoting children's health
Child's daily routine
If the rhythm in the hours of eating, sleeping, walking is repeated day after day, different types activity, then this has a beneficial effect on the state of the nervous system and on how all physiological processes occur in the body. Compliance with the regime disciplines children, improves their appetite, sleep, increases performance, and promotes health.
IN preschool institutions for each age group An educational program is provided, which necessarily includes various activities, hardening procedures, walks in the fresh air and other routine moments.
Particularly important in the daily routine is proper sleep. Lack of sleep negatively affects general health child: he becomes lethargic or, conversely, too excitable and capricious. Children should be put to bed at the same time, then they develop the habit of falling asleep calmly and quickly. It is important that the room is quiet, clean and well ventilated (during nap the windows open).
According to Yu.A. Ermolaeva preschool age covers the period of life from 3 to 6 - 7 years. At this time, intensive biological development of the child’s body occurs. The child’s body is constantly in the process of growth and development, which occurs continuously in a certain regular sequence.
A child at different periods of life is characterized by certain anatomical and physiological characteristics, the totality of which leaves an imprint on the educational and educational process (1985).
Physiological characteristics of preschool children
The first 7 years of a child’s life are characterized by intensive development of all organs and systems. A child is born with certain inherited biological properties that form the basis for further physical and mental development, and the determining factor from the first months of life is the environment and upbringing of the child.
A feature of the central nervous system of a child in the first years of life is the incompleteness of the morphological structure and functional development of the cerebral cortex. The completion of these processes occurs in subsequent years under the influence of external and internal stimuli.
The nervous system of preschool children is characterized by high excitability and weakness of inhibitory processes, which leads to widespread irradiation of excitation throughout the cortex and insufficient coordination of movements. But long-term maintenance of the arousal process is not yet possible, and children quickly get tired.
The first years of children's lives are characterized by a lack of intersystem connections in the body. When cortical processes are weak in children, subcortical excitation processes predominate. Children at this age are easily distracted by any external irritation. Voluntary attention is very short-lived, from 3 to 20 minutes, so the use of imitative reflexes, emotionality of classes, and play activities are of great importance for the formation of motor skills.
Speech development is of particular importance in a child’s behavior. Until the age of 6 years, reactions to direct signals predominate in children, and from the age of 6 speech signals begin to dominate (A.S. Solodkov, 2005).
The development of sensory systems mainly occurs during preschool and primary school age. The visual sensory system develops especially quickly during the first 3 years of life, and then its improvement continues. As the child grows and the relationship between visual information and motor experience improves, the assessment of spatial depth improves. The field of vision increases sharply from the age of 6 years.
The child's auditory sensory system has vital importance for the development of speech, providing not only the perception of the speech of strangers, but also playing the formative role of a feedback system in one’s own pronunciation of words. Her excitability to verbal signals increases especially noticeably at the age of 4 years and continues to increase by 6-7 years. The acuity of hearing and the ability to differentiate sounds increases (N.I. Obreimova, 2000).
The motor sensory system is one of the first to mature in humans. The formation of proprioceptors - muscle spindles and tendon receptors begins from 2 - 4 months intrauterine development and continues after birth until 4 - 6 years. This dramatically improves the ability to regulate motor activity and developing new skills.
Many children exhibit high vestibular resistance to rotation and rotation. The earlier emergence of contacts of the vestibular sensory system with the motor system and with other sensory systems allows the child to master the basic fund of movements by the age of 2-3 and begin physical exercises from the first years of life (A.S. Solodkov, 2005).
In preschool age, the musculoskeletal system is intensively formed. By the age of 5 - 6 years, the shape of the spine is like that of an adult, but the fixation of the spine is still imperfect (N.I. Obreimova, 2000). The calcium content in the skeleton increases, so ossification of the skeleton occurs, but there is still a lot of cartilage tissue in it. The intensity of metabolism in bone tissue decreases. In the bones and skeletal muscles of children there are a lot of organic substances and water, but few mineral substances, so the bones are flexible, therefore, during this period, incorrect postures, overwork, excessive overload when performing physical exercises can cause sudden disturbances in posture due to improper redistribution of muscle-ligamentous tone apparatus (Z.V. Lyubimova, 2003).
In the first years of life in children, the tone of the flexor muscles exceeds the tone of the extensors. It's difficult for children long time maintain an upright posture. The muscles of the limbs are relatively weaker than the muscles of the trunk. Insufficient development of the muscular-ligamentous apparatus of the abdominal press can cause the formation of a sagging abdomen and the appearance of hernias when lifting weights. The muscle strength of preschool boys is equal to the muscle strength of girls (A.S. Solodkov, 2005).
The mass of muscle tissue gradually increases. In the period from 4 to 7 years, there is a significant increase in muscle mass and, accordingly, the contractility, strength and performance of muscles increase, therefore, according to the recommendations of L. Kechedzhieva (1985) and others, exercises for the muscles of the shoulder girdle and hip joints, a child is 5-7- summer age can be performed daily from 20 to 30 times, and for the trunk muscles - from 40 to 60 times, in separate series of 6-8 or 12-16 times. The large volume of work performed causes noticeable changes in metabolism and in the functioning of the body’s functional systems, expanding the mechanisms of adaptation not only to physical activity, but also to action various factors external environment, helps to improve overall performance.
The cardiorespiratory apparatus is of great importance in ensuring human life. Children of preschool age are distinguished by small heart sizes and weakness of the heart muscle, which in turn determine low COVR, and in combination with high elasticity and wide lumen of blood vessels - low blood pressure. With age, the cardiovascular system becomes more efficient. The mass of the heart and the force of heart contractions increase, the heart rate decreases: at 3 years it is 105 beats per 1 minute, at 5 years - 100 beats per 1 minute, at 7 years - 85-90 beats per minute. The heart rate value is very labile and easily changes with any external stimulation (Z.V. Lyubimova, 2003).
The child's lung tissue has little extensibility, and the bronchial tree is not sufficiently formed. The chest is cone-shaped and has a small excursion, the respiratory muscles are weak. All this complicates external breathing, increases energy consumption for inhalation and reduces the depth of breathing. Children breathe frequently and shallowly. Due to the high excitability of children, the breathing rate increases extremely easily during stress and emotional outbursts. At the end of preschool age, the formation of chest, abdominal breathing appears.
Energy metabolism in preschool children significantly exceeds the level of metabolism in adults, decreasing most sharply in the first 5 years and less noticeably throughout subsequent life. Daily energy expenditure increases with age.
At the age of 6-7 years, there is a slight acceleration in growth, the so-called. the first physiological stretch, at the same time differences in the behavior of boys and girls appear. Glands such as the thyroid, adrenal glands, and pituitary glands take an active part in these processes. The “preparation” of the gonads for the period of puberty begins (N.I. Obreimova, 2000).
Thus, over the period from 3 to 7 years, the third, fifth and seventh years of life are distinguished, when not only quantitative growth occurs, but also a significant restructuring of functions, while the restructuring of the activity of the main energy-supplying systems precedes that in the motor function, which creates the preconditions for targeted impact during these critical periods of funds physical education. It has been proven that the age from 4 to 5 years is characterized by the greatest intensity and harmony of development.
SKIN AND SUBCUTANEOUS FIBER
Newborn babies: the skin is soft, velvety, elastic, pink; rich in blood vessels and capillaries. Sweat glands are poorly developed, sebaceous glands are active, which leads to rapid overheating or hypothermia of the child. Newborns have easily vulnerable skin. Subcutaneous fat tissue is well developed and denser than it will become in the future.
Infants: the skin is still very tender and easily vulnerable. Thermoregulation is imperfect (overheating or hypothermia of the body).
Older toddlers: the skin is thin, delicate, its absorption capacity is very high. You have to be very careful with medications in the form of ointments.
Preschool children: The skin gradually thickens, but it is still possible to become easily cold or overheated.
Children of primary school age: sweat glands are finally formed, the child is less susceptible to hypothermia and overheating. Large accumulations of fat cells appear in the chest and abdomen, which, with poor nutrition, is aggravated by general obesity.
Children of senior school age: skin like an adult.
MUSCULAR SYSTEM
Newborns: increased tone - arms bent at the elbows, legs pressed to the stomach. The muscles in the neck are weak and cannot support the head.
Infants: if the position of a newborn baby remains at rest for 2.5 months, consultation with a neurologist is necessary.
1-3 years: the mass of the muscular system increases, but fine movements (of the fingers) are still difficult to achieve.
3-11 years: muscle strength increases, performance improves. Fingers can do more delicate work (writing, modeling).
11-17 years: the muscular system becomes like that of an adult.
BONE SYSTEM
Newborns: fragile. Bones are easily bent when improper care for the child. There are non-ossified areas in the skull - fontanelles. The head is 1-2 cm larger than the chest circumference, the arms are much longer than the legs. The chest is barrel-shaped, the ribs are located horizontally and consist mainly of cartilage, as well as the spine, which does not yet have physiological bends.
Infants: by 1-2 months the small fontanel closes, and by the year the large one closes. By 6-8 months, teething begins. Their appearance is accompanied by a slight fever, anxiety, insomnia and malaise.
1-3 years: By 2.5 years, baby teeth have fully erupted. The shape of the chest changes, the ribs are positioned more obliquely, and the curves of the spine are formed. The growth of the pelvic bones continues.
3-7 years: the spine already corresponds in shape to an adult, but the child’s skeleton is still fragile. Strict control over the child’s posture is necessary. Scoliosis - curvature of the spine - begins at this age. The formation of the chest is completed.
7-11 years: chest volume increases. By the age of 11, differences in the shape of the pelvis appear - in girls it is wider.
12-17 years: the shape of the chest and pelvis approaches their structure in adults. Bones are stronger and less elastic. Fixing something is more difficult.
RESPIRATORY SYSTEM
Newborns: the lungs are underdeveloped, breathing is shallow and occurs mainly through the diaphragm. Therefore, breathing is easily disrupted by the accumulation of gases, constipation and tight swaddling. Breathing is frequent: 40-60 breaths per minute. The mucous membranes of the respiratory tract are delicate and contain a large number of blood vessels. The nasal passages are narrow, as are the trachea and bronchi. The auditory tube is wider and shorter, so newborns often develop otitis media. There are no frontal and maxillary sinuses, so newborns do not have sinusitis or sinusitis.
Thorax: lungs are more developed. Up to 3 months, the respiratory rate is 40-45 breaths per minute, at 4-6 months - 35-40, at 7-12 months - 30-35. The respiratory organs of a small child are very different from the respiratory organs of an adult. The mucous membrane of the nasopharynx and oral cavity is rich in blood and lymphatic vessels, which creates favorable conditions for the development of swelling and various types of inflammation.
A child of the first year of life does not know how to breathe through his mouth, so when he has a runny nose, he suffocates while sucking.
1-3 years: the trachea and bronchi are still narrow, there remains a danger of a sharp narrowing of their lumen and breathing disorders due to bronchitis, tracheitis, acute respiratory infections, and influenza. The respiratory rate by 3 years is 25-30 inhalations and exhalations per minute.
3-7 years: breathing is deeper and rarer. By the age of 7, it reaches 23-25 inhalations and exhalations per minute.
7-11 years: the structure of the lung tissue is finally formed. The diameter of the trachea and bronchi increases and in case of diseases of the respiratory system, swelling of the mucous membrane no longer poses a serious danger. Respiration rate - up to 20 breaths per minute.
12-17 years: the respiratory system is almost like that of an adult.
THE CARDIOVASCULAR SYSTEM
Newborns: With the birth of a child, changes occur in the circulatory system. The umbilical vessels and vein stop their activity, and the intrauterine blood flow channels close. With the first breath, the pulmonary circulation begins to work. The pulse rate is 120-140 beats per minute, when feeding or crying it increases to 160-200 beats. Blood pressure at the beginning of the first month is 66/36, and by the end of the month it is 80/45.
Thoracic: up to 1 year of age, the mass of the heart increases. The heart rate gradually decreases to 125 beats per minute. Blood pressure increases to 90/63.
1-3 years: 1 year - pulse 120, at 3 years - 105 beats per minute. Blood pressure by 3 years - 95/60.
3-7 years: pulse by 7 years - 85-90, blood pressure - 104/67.
7-11 years: heart rate decreases to 80 beats per minute. The blood pressure of an 11-year-old child is on average 110/70.
11-17 years: pulse rate - 60-80 beats per minute, i.e. like an adult. Blood pressure by the age of 17 is 120/70. Again, like an adult.
Considering even this limited information, it becomes obvious that even one fact of differences in the hydration of tissues of children's and adult organisms gives reason to assume that the distribution of medicinal substances in them is different, especially those that are soluble or easily solubilized in the presence of natural cosolvents.
DIGESTIVE SYSTEM
Newborns: functionally immature. Metabolism is increased, so minor errors in the diet of a breastfeeding mother and the child’s diet can cause digestive upset (dyspepsia). Digestive glands have not yet developed. The intestinal muscles are still poorly trained and the movement of food through it is slow. In the first 10-20 hours of life, the child’s intestines are almost sterile, then they begin to colonize it with the bacterial flora necessary for digesting food. The liver is relatively large.
Infants: up to 6 months, the child eats mainly breast milk, boiled water is given. Then they gradually begin to give juices and cereals. New foods should be introduced into the diet very carefully.
1-3 years: more complex food is digested, the frequency of bowel movements is 1-2 times a day.
3-11 years: digestive system approaches that of adults, and by the age of 11 is no different from it.
THE IMMUNE SYSTEM
Newborns and infants: the child receives some of the immune substances from the mother and through breast milk. But in general the immune system imperfect, i.e. the child is poorly protected from infections.
1-3 years: the formation of immune cells increases, which dramatically increases the body's resistance.
3-7 years: the child’s body produces immune cells in sufficient quantities, so many diseases occur more easily.
7-11 years: the body's defenses are well developed. Laboratory indicators are almost the same as for adults.
URINARY ORGANS
Newborns: By the time of birth, the kidneys, ureters and bladder are quite well formed. However, severe stress experienced by a child during childbirth short-term disrupts metabolism. The child urinates only 5-6 times a day. From the second week, the metabolism gradually stabilizes, the number of urinations increases to 20-25 times a day.
Chest: volume Bladder increases, the walls become more elastic. By the end of the first year, the number of urinations decreases to 15-16 times a day.
1-3 years: the structure of the kidneys improves, and the number of urinations decreases to 10 times a day. Healthy child regulates the act of urination independently. Most drugs and/or their metabolites are excreted by the kidneys. Kidney function in newborns is reduced, so excretion of many substances in the urine occurs less intensely than in adults.
Renal blood flow increases with age as a result of an increase in cardiac output and a decrease in total peripheral vascular resistance. Renal blood flow in newborns is 5-6% of the cardiac output, while in adults it reaches 15-25%. At birth, renal blood flow is 12 ml/min (0.72 l/h), and by the 1st year it increases to 140 ml/min (8.4 l/h).
At birth, glomerular filtration rate is directly proportional to gestational age. The glomerular filtration rate in all full-term newborns at the time of birth is 2-4 ml/min, in premature infants it is 1 ml/min. In the first 2-3 days after birth, it increases to 8-20 ml/min and 2-3 ml/min, respectively. Glomerular filtration reaches adult levels by 2.5-5 months. The increase in glomerular filtration rate after birth is due to a number of reasons: an increase in cardiac output and blood pressure, a decrease in total peripheral vascular resistance, an increase in the surface area capable of filtration, and the size of membrane pores.
The function of the renal tubules in newborns is also reduced (small size of the tubules and the number of functioning cells, low blood flow in the outer part of the cortex, immaturity of energy-supplying processes). The tubular apparatus matures later than the glomerular apparatus. The excretion of paraaminohippuran, which is secreted by the proximal tubules during the first year of life, increases 10-fold, reaching adult levels by 8 months. Drugs that are excreted from the body by tubular secretion include aminoglycosides, cephalosporins, penicillin, digoxin, and furosemide. They should be used with particular caution in the presence of impaired renal function.
7-11 years: kidney structure as in adults. The daily amount of urine gradually increases.
NERVOUS SYSTEM
Newborns and infants: immature nervous system.
1-3 years: little man begins to become aware of himself and the world around him.
3-7 years: the foundations of intelligence are laid.
7-11 years: analytical capabilities expand.
12-17 years: analytical and abstract thinking develops.
Biotransformation of drugs occurs mainly in the liver, as well as the adrenal glands, kidneys, intestines, and skin. As a result of biotransformation, more polar molecules are formed, which are quickly excreted from the body in urine or bile. However, during metabolism, some drugs are converted into pharmacologically active substances.
In a child’s body, the same biochemical changes occur with medicinal substances as in adults, however, the intensity of metabolic processes can differ significantly. In particular, in newborns, the rate of oxidative reactions involving cytochrome P450 and NADP-cytochrome C reductase is reduced by half, so the biotransformation of drugs, which is based on these reactions, slows down. Due to the relatively low rate and biotransformation of medicinal substances, their excretion in unchanged form increases.
The state of other enzyme metabolic systems (in addition to oxidative ones) in children is less studied. Conjugation reactions with sulfates and glycine proceed in the same way as in adults. At the same time, the activity of glucuronyl transferase, alcohol dehydrogenase, and esterase in newborns is reduced. The elimination of drugs whose biotransformation involves the listed enzymes slows down in a newborn, and their half-life increases. Such drugs may be affected by other enzymes that have higher activity. Thus, in 2-3-day-old full-term infants, the conjugation of paracetamol with glucuronic acid is reduced, but the drug is actively conjugated with sulfates.
In children in the first years of life, glucuronidation of salicylamide and chloramphenicol is also impaired. Phenobarbital may induce glucuronyl transferase activity in neonates.
The biotransformation of some drugs in newborns differs from that in adults. Thus, the methylation reaction in the fetus and newborn has important functional significance, so theophylline is not demethylated as in adults, but is methylated into caffeine.
If attention is always paid to the anatomical and physiological characteristics of a child when studying the pathogenesis of diseases and their clinical manifestations in various periods of childhood when justifying differential diagnostic criteria, then the functional characteristics of the child’s body, taking into account the pharmacokinetics of drugs, often remain out of attention or are ignored. The pediatrician loses sight of the direction and nature of metabolic processes in the body of a sick child and does not take into account the peculiarities of biotransformation of the prescribed drug. The situation is aggravated by the fact that when prescribing several medications to a child at the same time, their compatibility, potentiation, or, conversely, the leveling of the pharmacological effect is not always taken into account. But, unfortunately, polypromasia in real life is the rule, not the exception.
Polypharmacy itself causes considerable difficulties, since drug interactions in children have been little studied, although the pediatrician is focused on possible manifestations of both antagonism and synergism of drugs. Some drugs affect the absorption and metabolism of vitamins, especially fat-soluble ones, which is not always corrected in a timely manner in sick children. For example, laxatives, cholestyramine and similar lipid-lowering drugs interfere with the absorption of vitamins A, D, and E. Anticonvulsants and antibiotics used to treat H. pylori infection significantly alter the metabolism of vitamin K, and at the same time the absorption and metabolism of water-soluble vitamins are disrupted.
Converting drugs into children's body different than in adults. Many detoxification enzyme systems mature gradually during child development. These, in particular, include the microsomal oxidation system of cytochrome P-450 oxidase in the liver, as well as the enzyme systems of glutathione reductase, glutathione transferases, UDP (uridine diphosphate glucose)-glucuronyltransferase and others. With age, the sensitivity of tissue receptors to hormones, hormone-like and other drugs with a pronounced biologically active effect changes.
What factors influence the kinetics and metabolism of drugs? With age, the relative volume of fluid distribution in children changes; extracellular fluid predominates, which determines the distribution characteristics of both water-soluble and fat-soluble drugs in the child’s body. The rate of maturation of liver enzyme systems, which convert drugs into inactive and water-soluble forms, slows down. IN childhood low renal glomerular filtration, limiting the processes of excretion of drugs and their metabolites in the urine, the ability of liver proteins (ligandins) and blood plasma to bind drugs and xenobiotics is reduced, the permeability of the membrane structures of capillaries and the blood-brain barrier is increased. When prescribing treatment, it is also necessary to take into account the state of the endocrine glands in children, which, as is known, play an important role in the metabolism of drugs. With a decrease in the functional capacity of the thyroid gland, especially congenital hypothyroidism, the metabolism of drugs also changes to one degree or another.
Pharmacogenetics is one of the little-studied aspects of pediatrics, although it is the genetic factors that determine the processes of metabolism, reception, immune response, etc. that largely determine the tolerability of drugs, their safety and effectiveness.
An effective drug, the cost of which can be quite high, is often not safe for a child. For example, treatment regimens used in adults for gastroduodenal diseases associated with the notorious H. pylori cannot always be extrapolated to children, since they may use tetracycline antibiotics. Side effects The effects of these drugs on the child’s body are well known. In pediatric gastroenterology, the safety aspect of pharmacotherapy receives sufficient attention. At the same time, these aspects, unfortunately, are not always known to pediatricians. Using the example of cimetidine, a first-generation histamine H2 receptor blocker, I would like to remind you that in addition to effectively reducing the concentration of hydrochloric (or hydrochloric) acid in the vast majority of children, the drug caused numerous undesirable effects. In addition to liver and kidney dysfunctions, hematological and immunological abnormalities, pronounced neurovegetative and psycho-emotional changes were observed in children. The drug had a negative effect on the endocrine glands. It was precisely the risk of a negative impact on the development of gonadotropic function in children in the pre- and pubertal periods that kept pediatric gastroenterologists from widely using cimetidine in the treatment of patients with gastroduodenal diseases. The reason for the various undesirable reactions of this drug was that its related receptors are widely distributed in liver cells, endocrine organs, nervous tissue and even lymphocytes. New generations of the same group of drugs, such as ranitidine, famotidine, have exceptional selectivity for H2 receptors and, with the exception of individual intolerance, are safe and effective in childhood. In connection with the above, I would like to once again draw attention to the fact that the issue of prescribing medications should be decided by a specialist.
Rule 1
Treatment of the child should be carried out at the most optimal level using the most effective and safe medications for children. Therefore, most often, children should be prescribed medications that have been proven over the years: infusions and decoctions from medicinal plant materials, aromatic waters, activated carbon - internally, furatsilin, lycopodium - externally and similar drugs.
The most convenient dosage forms for young children are in the form of syrups, drops or suspensions. Once in the intestines, liquid medications spread over a larger area of the mucous membrane and are better absorbed. Suspensions and medicinal syrups, however, also pose considerable danger. Since they are quite tasty, kids tend to drink more of them. It happens that a child, unnoticed by his parents, swallows a whole
a bottle of the medicine he liked. This can lead to serious consequences.
Rule 2
All medications, and especially medications for children, must be stored in places inaccessible to them.
Candles are also quite convenient for small children to use. However, it is more natural for the body when drugs enter it through the mouth, rather than through the rectum. It is better to use suppositories only in cases where the child cannot swallow the medicine and when it is necessary for it to act immediately. Then they are inserted into the baby's anus, laying him on his side or back and pressing his bent legs to his stomach. You need to hold it in this position for half a minute so that the candle does not slip out.
Knowledge age characteristics child development facilitates the construction of a physical education system at this age, helps the correct construction of physical education classes (drawing up programs, selecting and dosing exercises, choosing methods of physical and motor training, etc.). Helps to monitor physical and mental development children.
The first years of a child’s life are characterized by rapid growth and development of the body. Morphological parameters increase intensively: height and weight, chest girth (Table 1).
The weight of newborn girls is on average 3.3 kg, boys - 3.4 kg, the weight triples by year. In the second year of life, the child gains 2.5-3.5 kg, in the third year - 1.5-2.0 kg. In the fourth, fifth and sixth years of life, the annual increase is 1.5-2.0 kg. From the age of 7 years, an increased increase in body weight begins.
Like changes in mass, growth gains are uneven. The average height of newborns is 50 cm. During the first year of life, the child’s height increases by 25 cm. During the second and third years, it increases by 8 cm annually, and from 4 to 7 years, the annual increase in height is 5-7 cm.
Table 1 Average body weight and height of healthy children of early and preschool age (according to Yu.F. Zmanovsky, 1989)
When a baby is born, the head circumference is greater than the chest circumference. The head circumference of a newborn child is 34 cm, and the chest is 33 cm. During the first year of life, the head circumference increases by 12 cm, becoming equal to 46 cm; in the second year, the head circumference increases by only 2 cm; over the next 4 years, the head circumference increases by another 3 cm, and by 6 years its value is 51 cm. By the end of the first year of life, the chest circumference reaches 48 cm, at 5 years - 56 cm , at 15 years old - 73 cm.
Age-related changes in body proportions. In a newborn, the length of the head is 1/4 of the total height, in a 2-year-old - 1/5, in a 6-year-old -1/6, and in an adult -1/8. In newborns, the length of the upper and lower limbs is approximately the same and amounts to 1/3 of the height. By the age of 7, the legs lengthen from 18 cm to 57 cm, i.e. more than three times. During the same period, the length of the arms increases a little more than 2 times and becomes equal to 41 cm. The torso increases to 37 cm, i.e. 2 times. Over the entire period of development, the length of the legs increases by 5 times, the arms by 4 times, and the torso by 3 times.
From 2-3 years of age, the formation of bone tissue with a lamellar structure begins. The process of skeletal ossification occurs gradually throughout childhood. The formation of physiological curves of the spine in the cervical, thoracic and lumbar regions continues throughout the preschool period (when the child begins to hold his head up, lie on his back, sit, walk). The spine of children is characterized by mobility; its physiological curves are unstable and smooth out when the child lies down. The soft mass of the skeleton is easily susceptible to influences that change its shape: incorrect position body when sitting, standing, lying down. Incorrect postures quickly become habitual, postural disturbances appear, which negatively affect the function of blood circulation and breathing, and abnormal bone growth occurs.
The skeletal system in children is richer in cartilage tissue than in adults. Therefore, the child’s bones are soft, flexible, do not have sufficient strength, are easily bent and become irregular shape under the influence of unfavorable external factors (physical exercise that do not correspond to the functional and age capabilities of children, clothes, shoes, furniture that do not correspond to the child’s height, etc.).
The formation of the arch of the foot begins in the first year of life, most intensively with the beginning of walking, and continues in preschool age.
During normal walking, the feet are placed in relation to the median (sagittal) plane of the body at an angle of up to 35 degrees. This is the most beneficial support. In most children, when walking, their feet are parallel, while in small children they are slightly turned inward. If the angle of the children's feet is wider than their own palm, then an overload is created on the inner arch of the feet under the weight of the body. This is one of the reasons for the subsidence of the arch, i.e. the formation of flat feet.
Therefore it is necessary to pay Special attention selecting appropriate shoes (with heels), using exercises to strengthen and properly form the arch of the foot.
Muscular system in a child early age is not yet sufficiently developed compared to an adult, and muscle mass makes up about 25% of his body weight, whereas in an adult it is on average 40-43%. In children of primary preschool age, the extensor muscles are underdeveloped and rather weak, so the child often takes incorrect postures: a lowered head, contracted shoulders, a stooped back. By the age of 5, muscle mass increases significantly, especially the muscles of the lower extremities, and the strength and performance of muscles increases. Indicators of muscle strength reflect both the characteristics of age-related development and the influence of physical education. The strength of the hand muscles increases from 3.5-4 kg at the age of 3-4 years to 13-15 kg by the age of 7 years. Already from the age of 4, differences in indicators between boys and girls are noted. The strength of the trunk muscles (dead strength) by the age of 7 increases almost 2 times from 15-17 kg at 3-4 years to 32-34 kg.
A feature of the central nervous system of a child in the first years of life is the incompleteness of the morphological structure and functional development of the cerebral cortex.
At this age, nervous processes are not strong and mobile enough, but conditioned reflex connections are very strong and very difficult to alter. Therefore, in the process of physical education it is necessary to teach children correct execution this or that exercise, since the acquired skill is firmly and permanently consolidated. Simple movements learned with errors will make it impossible in the future to correctly form more complex motor skills.
During the preschool period, there is a pronounced restructuring of the activity of the cardiovascular and respiratory systems to a more economical and efficient level of functioning, and therefore the capabilities of children in performing muscular activities increase.
In the first years of life, the child’s cardiovascular system undergoes significant morphological and functional changes. The weight of the heart increases from 70.8 g in children 3-4 years old to 92.3 g in children 6-7 years old, due to which the force of heart contractions increases and the performance of the heart increases.
The number of heartbeats in newborns is 120-140, at 1 year 120-125, at 2 years 110-115, 3 years 105-110, 4 years 100-105, 5 years 98-100, 6 years 90-95, 7 years 85 -90. Gender differences in heart rate were noted: in boys it was lower than in girls of the same age.
Blood pressure increases with age: in the first year of life it is 80-85/55-60 mm Hg. Art., at the age of 3-7 years it ranges from 80-110/50-70 mm Hg. Art. The performance of the heart increases, the adaptive ability to physical activity increases: the value of indicators decreases of cardio-vascular system(pulse, blood pressure, stroke and minute volumes of blood circulation) in response to standard muscle load, the recovery period is shortened.
The respiratory rate decreases with age: by the end of the first year of life it is 30-35 per minute, by the end of the third - 25-30, and at 4-7 years - 26-22. With age, the depth of breathing and pulmonary ventilation increase, and oxygen consumption almost doubles. These data indicate that the functional capabilities of children are great and fully meet the needs of growth and development.
Increasing the level of morphological and functional development of the main body systems also ensures an increase in the physical performance of children. Ability to perform continuous operation increases from 10 to 25-30 minutes, while the total amount of work increases by approximately 2.5 times.
Active movements in two-year-old children account for 70% of their waking time, and in three-year-olds - at least 60%. With age, the number of movements in children increases. The intensity of motor activity - the average number of movements per minute - is approximately 38-41 in children 2 years old, 43-50 - 2.5 years old, 44-51 - 3 years old. Children are characterized by frequent changes of movements and postures - up to 550-1000 times a day. Taking into account this feature, it is necessary to provide a variety of motor activities for children, creating conditions for different movements.
Failure to comply with the age characteristics and capabilities of the child in the learning process, etc. accelerating the pace of children's learning causes unbearable stress on the body, which is harmful to health and neuropsychic development children. Knowledge of the developmental features of the body of preschool children is prerequisite when organizing physical education classes.
A person develops throughout his life, but especially intense changes occur in childhood. The development of a growing organism is subject to certain patterns inherent in different age periods.
In children under 7 years of age, three age periods are conventionally distinguished, differing in the developmental features of both individual organs and systems and the entire organism as a whole: period infancy- from birth to 1 year, the period of early childhood - from 1 year to 3 years and the period of preschool age - from 3 to 7 years.
For each age period They have their own characteristics of anatomical structure, physiological functions and metabolism, which must be taken into account when organizing the child’s nutrition.
The period of infancy is characterized by rapid growth, development and improvement of all organs and systems.
A full-term baby is born with an average body weight of 3200-3400 g and a height of 49-51 cm. Boys are usually larger than girls.
The child grows most vigorously in the first months of life, then the growth rate slows down somewhat. So, in the first 3 months of life, a child on average gains 3 cm per month in height, from the 4th to the 6th - 2.5-2 cm per month, in the second half of the year - 2-1.5 cm per month. month. Thus, by 6 months of life, the child grows by 15-16 cm, and over the entire first year of life - by 25-27 cm.
The increase in body weight, as well as growth, is more intense at the beginning: in the first month of life, the child adds 600 g, during the second and third months of life - 800-900 g, and then during each subsequent month the child gains body weight by 50 g less than the previous one.
Thus, a child born with average body weight doubles it by 5 months of life and triples it by 11-12.
To find out what height and body weight a child should have in the first year of life, it is necessary to add the corresponding indicators of increase in height and body weight over the life period to the indicators at birth. In this case, it is convenient to use the table of average indicators of increase in height and body weight of children in the first year of life.
The first year of a child’s life is also characterized by the intensive development of the central nervous system, the formation active movements, various skills and abilities. At the age of one month, the baby already holds his head well, reacts to sounds, and smiles. At 3 months, the range of movements increases: the child turns from back to side, begins to grasp objects, clearly determines the direction of sound, and recognizes loved ones. At 6 months, the baby rolls over well from back to stomach and back, begins to crawl, and pronounces individual syllables. At 8-9 months, the child sits down independently, stands up and moves around with support, and babbles a lot. At the age of one year, the baby usually begins to walk without support, pronounces 10-12 words, knows how to drink from a cup, and tries to eat independently with a spoon.
During the first year of life, many significant changes occur in the child’s body, including the maturation and formation of all organs and tissues. The bone skeleton acquires greater density, muscle mass increases, the subcutaneous fat layer develops, the skin thickens, becomes less vulnerable, and the functions of the respiratory and cardiovascular systems improve.
After 6 months, the child’s first teeth erupt; by the age of one year, the child usually has 8 teeth.
The gastrointestinal tract continues to develop. Compared to the first months of life, the volume of the stomach increases significantly, reaching 250 ml by the year of life (30-35 ml in a newborn). Due to the introduction of new types of food into the child’s diet, the secretion of digestive juices increases and their activity increases. The processes of breakdown and absorption of nutrients are improved. Almost by the end of the first year of life, the child can receive all basic food products.
By the age of one year, the frequency of stools decreases to 1-2 times a day (in a newborn, 4-5 times a day). In some children, especially when artificial feeding, stool may be every other day. If the child's general condition is good, this should not cause alarm and does not require any intervention.
Early age is the period of a child’s life from 1 to 3 years.
During this period, there is a gradual improvement in all the functional capabilities of the child’s body. However, young children are still very vulnerable, susceptible to various diseases, including nutritional disorders. A baby at this age is easily susceptible to any environmental influences.
Pace physical development of a child in the second and third years of life slow down somewhat. During the second year of life, the child’s height increases by 10-11 cm, body weight - by 2.5-3 kg, in the third year of life these figures are 7-8 cm and 2 kg, respectively.
In young children, maturation and differentiation of bone and muscle tissues continue, and motor skills become more complex and improved. During this period of life, the child masters walking, running, and jumping well. By the age of three, he masters more complex skills: he eats, dresses himself, begins to fasten buttons, tie shoelaces with a little help from an adult.
The development is especially noticeable intellectual abilities child. His stock of ideas is significantly enriched, his conscious attitude to the surrounding reality expands, his speech quickly develops, and the need to communicate with other children arises. By the age of three, the baby begins to use complex sentences, knows and names the four primary colors, and acquires the necessary hygiene skills. In communication with peers, elements of role-playing play appear.
In children older than one year, the digestive organs are significantly improved. By the age of two, the child already has 20 teeth and can chew food well. The volume of the stomach in 2-3 year old children increases to 350-400 ml. The digestive capacity of the gastrointestinal tract increases. All this allows you to introduce a more varied range of products into your child’s diet. However, the susceptibility of a young child to various eating disorders remains high. When he deviates from the diet, he easily experiences digestive disorders in the form of vomiting and loose stools.
Preschool age refers to the period of a child’s life from 3 to 7 years. Children of this age differ markedly in development from young children. They undergo further development and improvement of the body.
The physical development of children during this period is uneven. At the age of 4-5 years, the growth rate slows down somewhat, the child grows by an average of 4-6 cm per year, and during the sixth or seventh year of life, the increase in height reaches 8-10 cm per year. The rapid increase in the growth of children aged 6-7 years is called the first period of extension. It is associated with functional changes in endocrine system(strengthening the function of the pituitary gland). By the age of 7, the child’s upper and lower limbs noticeably lengthen, and the chest circumference increases.
Body weight gain in children by the age of 4 slows down somewhat and averages 1.2-1.3 kg per year, and then it increases again: in the fifth year of life, the child gains an average of 2 kg, in the sixth - 2.5 kg, for the seventh - about 3.5 kg. By the age of 6-7 years, the child’s body weight has doubled compared to the weight at one year of age.
In preschool children, further development of the musculoskeletal system is noted. Bone tissue becomes denser, muscle mass increases. By the age of 5, the muscles of the lower extremities increase significantly, their strength and performance increase. The contractility of muscles improves and their strength increases.
The development and differentiation of the central nervous system is expressed in the improvement of static and motor functions, and the development of coordination of movements. Preschool children are more resilient to physical activity compared to young children. Their speech is well developed, children of this age already have certain skills in self-care, work, and are prepared for school.
Disease resistance in preschool children is much higher.
By the end of preschool age, the activity of the digestive tract in children reaches the level of an adult. By the age of 7, the child's permanent teeth erupt. From the age of 6-7 years, the replacement of all milk teeth begins. By the age of 5-7 years, the volume of the stomach reaches 400-500 ml, its muscle layer increases. The salivary glands function actively, the amount of digestive juices increases significantly and their enzymatic activity increases. Children of this age are much less likely to experience gastrointestinal disorders.
