What is meant by the concept of physical development. Physical development Definition. Indicators of a comprehensive assessment of the health of children and adolescents

In modern conditions, physical development is considered as one of the main criteria for the health of a separate person and the population as a whole.

Meaning and widespread useindicators of physical development is that, in contrast to others (morbidity, mortality, disabilities), they are direct, positive health characteristics.

The literature meets several approaches to definitionthe concepts of "physical development".

Regarding the physical development of a separate individual, we give two definitions:

I. S. Chance:Physical development is a complex of functional and morphological properties of the body, which in the end and determines the supply of its vitality.

Exhaustive is the definition E.Ya. Belitsky:Physical development is a set of signs that characterize the level and dynamic changes in a number of morphological, functional properties of a separate individual and groups of people expressed in the form of general and group characteristics (physical development standards).

State of physical developmentcan be considered as the result of the interaction of internal (endogenous) and external (exogenous) factors. To the first one belong:

Heredity, mother's health;

Physical condition of parents;

Features of intrauterine development.

To the second:

Natural climatic;

Socio-economic (economic development of society, working conditions and life, the nature of the profession, and the like).

Information on physical developmentit is used in the practical activity of doctors of various specialization, primarily pediatricians and specialists in the field of hygiene of children and adolescents.

Observation of physical development begins with the moment of the child's birth. In the future, it is carried out in children's clinics, pre-school institutions and schools, secondary and higher educational institutions, while calling for military service, when conducting targeted and periodic medical examinations, as well as with special sampling studies of the health of various groups of the population.

Indicatrics of physical development, especially in combination with rates, mortality, morbidity, are not only the criteria for public health, but also the criteria for the effectiveness of therapeutic and recreational activities.

These materials make it possible to observe the trends in the age development of children and adolescents.

There are biological and morpho-functional development of the child. Biological developmentevaluate with such criteria:

Growth (body length standing);

Dynamics of body mass during the year;

The change in dairy teeth for constant teeth;

Osforming brushes according to radiographs;

The degree of development of secondary sexual signs;

The term of the first menstruation in girls.

According to the above criteria for each age, the biological development standards are developed with which the actual data of a particular child compares. After that is carried out evaluation of biological developmentin comparison with the passport data on a three-point scale: looms, corresponds, ahead.

For the purpose of evaluation morpho-functional development of the childcriteria are used:

Growth (body length standing);

Body mass;

Chest size;

Compliance of the aforementioned signs of each other.

The above-mentioned parameters are also developing agent standards for the state and individual regions. With them compare the data obtained, and is carried out evaluation of morpho-functional developmenton a three-point scale: harmonious, disharmonious and very disharmonious.

It applies to monitor the physical state of the adult population and the study of the peculiarities of the physical development of various contingents and the influence of concrete factors.

When conducting mass medical, surveysapplied complex signsto assess physical development:

anthropometric -height, body weight, chest size; With in-depth studies - additionally growth sitting, head sizes, shoulder length, forearm, shin, hips;

functional, physiometric -the life volume of the lungs (spirometry), muscular power of the brush (dynamometry);

somatoscopicbody structure, muscle development, thoracic shape, feet, severity of secondary sexual signs, pulse, blood pressure, and the like.

Statistical processingthe materials obtained are carried out by methods of variational statistics by compiling the variational series, the regression equations, and the like.

Analysis of the data obtained is carried out using:

Sigmal assessment;

Individual assessment on the regression scale.

The latter method is exhaustive, for it makes it possible to take into account various signs in relationships, allocate persons with harmonious and disharmonious development.

Indicators of physical developmentin modern conditions are not a component of official statistical reporting,that does not allow constantly evaluating the state of the indicator on the population of the whole country. This can be done on the basis of special sample studies, which are conducted in such directions:

dynamic observationfor the physical development of the same contingents;

definition of patternsphysical development in various age-age groups and dynamics for a certain period of time;

development of regional agent standards withthe purpose of individual and group assessment of the physical development of children;

efficiency markwellness events.

Systematic observation in terms of physical development of the population over the past decades allowed to establish several most essential patterns:

1. occurs acceleration of the pace of physical developmentthe younger generation is an acceleration for which the characteristic change in the output level of physical development at birth, accelerating the pace of development in all age groups and earlier all-round development of children and adolescents.

2. The number of cases of disharmonious physical development increases,in particular, the disharmony of the pace of mental and physical development.

3. Increases partpersons S. overweightbodies affected by changes in the way of life, nutrition, hypodynamine, and the like.

Control questions

1. Approaches to the definition of the concept of "physical development".

2. The practical value of physical development indicators.

3. Methods and criteria for assessing the indicators of the physical development of children and adolescents.

4. Evaluation criteria and methods of statistical processing of physical development materials during mass surveys.

5. The main trends of physical development indicators over the past decades.

Section 5. Medical and Social Aspects of Essential Diseases

In the XX century, significant successes are achieved in the survival of humanity. Mortality of the population as a whole decreases, the average expected duration of life increases significantly. This process is unevenly distributed by individual countries of the world. In developed countries of the world, there is a "non-epidemic type of pathology", one of the signs of which is that most of the population of many countries die for reasons that are associated with chronic non-epidemic diseases (CHNZ): diseases of the circulatory system (BSK) and malignant neoplasms (3H). A significant particle is injured mortality, mortality rates from mental disorders. These are the so-called "civilization diseases".

Physical development is a complex of morpho-functional indicators, which are closely related to the physical performance and level of the biological state of the individual at a particular point in time.

The formation of physical development is based on the growth parameters, body weight, the proportions of the development of individual parts of the body, as well as the degree of development of the functional abilities of its body (the life capacity of the lungs, muscular power of hands, etc.; the development of muscles and muscular tone, state of posture, musculoskeletal The apparatus, the development of the subcutaneous fat layer, turgor tours), which depend on the differentiation and maturity of the cellular elements of organs and tissues, the functional abilities of the nervous system and the endocrine machine]. Historically, it is necessary to judge the physical development mainly on external morphological characteristics. However, the value of such data is immeasurably increasing in combination with data on the functional parameters of the body. That is why for an objective assessment of physical development, morphological parameters should be considered in conjunction with indicators of the functional state.

Aerobic endurance - the ability to perform the operation of medium power to perform and resist fatigue. The aerobic system uses oxygen to convert carbohydrates into energy sources. With long-term classes, fats are also involved in this process and, partly, proteins, which makes aerobic workout almost perfect for fat loss.

High-speed endurance is the ability to resist fatigue in the submaximal loads.

Power stamina is the ability to resist fatigue at sufficiently long power loads. Powerful endurance shows how much muscles can create repeated efforts and for which time to maintain such activity.

Speed-power endurance - the ability to perform sufficiently long-term strength exercises with maximum speed.

Flexibility - human ability to perform movements with a large amplitude due to the elasticity of muscles, tendons and ligaments. Good flexibility reduces the risk of injury during exercise.

The speed is the ability to alternate muscle contraction as quickly as possible and relax them.

Dynamic muscular power - the ability to the maximum quick (explosive) manifestation of efforts with greater burdens or own body weight. In this case, a short-term release of energy that does not require oxygen as such is happening. The growth of muscle strength is often accompanied by an increase in the volume and density of muscles - the "construction" of the muscles. In addition to aesthetic value, the enlarged muscles are less susceptible to damage and contribute to the control of weight, as the muscle tissue requires calories more than fat, even during the rest.

Dexterity - the ability to perform coordination and complex motor actions.

The composition of the body is the ratio of fat, bone and muscle tissues of the body. This ratio, in part, shows the state of health and physical preparation depending on weight and age. Excessive content of adipose tissue increases the risk of developing heart disease, diabetes, increase blood pressure, etc.

Growth-weight characteristics and proportions of the body - these parameters characterize the size, body weight, distribution of body mass centers, physique. These parameters determine the effectiveness of certain motor actions and the "suitability" of using an athlete's body for certain sports achievements.

An important indicator of the physical development of a person is the posture - a complex morpho functional characteristic of the musculoskeletal system. And also its health objective indicator is positive trends in the above indicators.

Physical development is characterized by changes in three groups of indicators.

Telecommunication indicators (body length, body weight, posture, volumes and shapes of individual parts of the body, weight of grease, etc.), which are primarily biological forms, or morphology, humans. physical development organism ontogenesis

2. Indicators (criteria) of health, reflecting morphological and functional changes in human physiological systems. The functioning of cardiovascular, respiratory and central nervous systems, digestive organs, and the mechanisms of thermoregulation, etc. has crucial importance on human health.
3. Indicators of the development of physical qualities (forces, high-speed abilities, endurance, etc.).

Approximately 25 years old (period of formation and growth) Most morphological indicators increase in size and improved the functions of the body. Then up to 45--50 years, physical development as it is stabilized at a certain level. In the future, as agreed, the functional activity of the body gradually weakens and worsens, the length of the body, muscle mass, etc. can be reduced.

The nature of physical development as the process of changing these indicators during life depends on many reasons and is determined by a number of regularities. Successfully manage physical development is possible only if these patterns are known and they are taken into account when building a physical education process.

The process of physical development is subject to the law of the unity of the body and the medium and, therefore, significantly depends on the living conditions of a person. The conditions of life are primarily among social conditions. The conditions for life, labor, upbringing and material support are largely affected by the physical condition of the person and determine the development and change in the forms and functions of the body. A well-known influence on physical development also has a geographical environment.

Of great importance for managing physical development in the process of physical education, the biological law of the exercise and the law of unity of forms and the functions of the body in its activities have. These laws are shipped when choosing funds and methods of physical education in each case.

Choosing physical exercises and determining the magnitude of their loads, according to the law of the exercise, you can count on the necessary adaptive restructuring in the body of engaged in the body. It takes into account that the body functions as a whole. Therefore, selecting exercises and loads, mostly electoral impact, it is necessary to clearly imagine all sides of their influence on the body.

You can give a lot of statements to protect what should be perceived uncorrectly. However, it will be much clear to imagine violations in this development. Perhaps it is a realization of the seriousness of the consequences will cause parents more closely to the health of the kid, and adults - to do in time.

Of course, a variety of factors affect physical development, but about half of these factors can change everything - this is a lifestyle, sports activity, the correct mode of sleep and nutrition, the right food.

If there are no systematic exercise activities in the child's life, most often he begins to lag in development. If a small lack of motor activity is observed, it can lead to a decrease in the capacity and growth of the body. If the shortage of movements is great - muscles can gradually be atrophy, developing obesity, other unpleasant consequences appear, which will entail more significant diseases. Physical development as a health indicator Especially clearly can be observed on the example of children and adolescents, comparing the state of their body with more active peers.

The absence of physical activity can lead to such unpleasant consequences as flatfoot, posture disorders. Especially often they develop from schoolchildren, so the task of parents is to provide a child for full-fledged sports training.

The habit of improperly sit, can lead to difficulties in the extension of the muscles of the neck, tibia, back. Physical development as a health indicator In this case, it is very clear: habits to take incorrect postures, lingering in it with hours, will certainly bring with them the consequences in the form of pain, violation of flexibility, reduced motor capabilities.

In case of insufficient and non-systematic developing physical exertion, a person is not able to withstand long loads, even in domestic conditions. Elementary lifting on the stairs without the help of the elevator causes shortness of breath, pain in the legs, back. Such examples mass. But if we consider physical development as a health indicator, it becomes clear - regular and systematic classes on a properly selected program will help to correct these disadvantages, returning the joy and ease of life.

Physical development and sport Inseparable, and in this article we will try to figure it out in the most detailed as possible.

Metabolism

Sport classes stimulate the metabolic process in the body, namely, the metabolism is an energy source for normal operation of all the functions and life processes of the organism without exception. Sport classes support the efficiency of the mechanisms that are carried out in the body the exchange of energy and substances, and without this it is impossible physical development and sport - The best tool for maintaining the health of all the livelihoods of the body.

Circulatory system

Of course, it is the heart of the main center of the human circulatory system, directly depends on his work. physical development - and sport Helps increase the performance and power of the heart muscle. The mechanism of exposure to the heart is simple: during classes, the mass and dimensions of the heart increase, since the walls of the heart muscle thicken, and the heart begins to work more active and rustier.

Respiratory system

Thanks to physical training, the body adapts to hypoxia (lack of oxygen), cells acquire the ability to work intensively even with a lack of oxygen.

Musculoskeletal system

Not only heredity causes physical outcome. On the physical development and sport It has a great influence, even when it comes to the musculoskeletal system.

In the process of sports training, the muscle blood supply is enhanced, the nervous system better controls their activity, muscle fibers grow.

It is as a result of the muscle system workouts that endurance and the ability to physical work are formed, with an increase in activity in children's and adolescence, the bone system changes, more active growth begins. The bones acquire high strength, become very resistant to both injuries and long-term loads. The performance of the body as a whole increases, and the cost of energy on its execution is reduced. Thanks to the correct breathing during training, the normal activity of all organs in the abdominal cavity is normalized, the correct system of classes helps to get rid of posture violations.

From the first second of life, the physical development of a person begins (a set of functional and morphological properties of the body, which determine endurance, legal capacity, reserves), and approximately 25 years it reaches its maximum.

The person is generally not separated: one of the most important health indicators is physical development.

Any factors are influenced by respectively. To be able to influence the course of development, you need to know about these factors maximum - this information will help strengthen the health of the body, make development more complete.

Physical development and health. What does it depend on?

External factors

Social conditions. Regional and national features of the style and lifestyle, degree of economic development, hygienic skills, cultural and educational level, etc.

The unfavorable development of the fetus inside the womb of the mother (presence, intrauterine effects, congenital vices).

Environmentally unsafe furnishings.

Eranny power, incorrect power mode.

Invalid recreation and labor (excessive fatigue, insufficient activity).

Lifeline lifestyle, lack of physical education.

Bad habits.

Internal factors

The presence of diseases.

Heredity (it was at the genetic level that the peculiarities of physical development are formed, this program is transmitted from one generation to another and may not be altered or improved). Physical development and health Mostly caused heredity precisely.

To improve physical development and health A person needs an integrated approach. It is difficult to talk about full-fledged development if the child did not adapt to the elementary rules of hygiene, ignore the need for physical education and practicing the use of monotonous food. Therefore, to physical development and health It was most complete, it is necessary:

To establish recreation and activity, sleep at least 8 hours a day.

Revise your diet, use more useful products and eliminate frankly harmful.

To do sports, conduct training regularly, the non-systematic approach will be ineffective.

Regularly undergo a medical examination in order to be able to objectively assess the condition of the body.

Get rid of bad habits, to establish a psychological climate surrounded (stress and irritability do not contribute to normal development).

We are interrelated: Properly organized physical exercises, health proceedings directly affect both the level of person's physical preparation and its health.

For an objective assessment of physical development, such parameters are used as: body weight, growth, the development of the functional features of the entire body (muscle strength of the hands, muscular tone, the development of musculature, state of posture, etc.). Accordingly, an integrated approach is needed for full physical development in which physical education is important.

Physical development and health Physical

Competent physical education contributes to the development of motor capabilities, increases the protective reactions of the body, improves the processes of life in general. With the right choice of the exercise system, its regular use, conducting hardware procedures, changing the mode and nature of nutrition, you can significantly improve the condition of not only those people who do not have serious health problems. These funds are effective in the presence of deviations in the work of the heart, with deviations in physical development (flatfoot, spinal deformation, posture defects).

Physical development and health mental

Exercise classes suggest constant mental development: regularly emerging cognitive situations, improvement of old techniques for exercising and mastering new ones, the ability to properly distribute forces, both at the time of all occupation and during the competition - all this does not pass without a trace. Also in training there are constantly situations in which a person should be made fast and rational solutions to overcome difficulties. All these skills and skills can be successfully used in everyday life, bringing all new life experience.

Physical development and health moral

If physical education classes are properly organized, they have a positive effect on the formation of moral qualities. The ability to bring started to the end, discipline, strong will, perseverance, the ability to regard the initial failures as an experience in the way to goal - all this brings up the ability to overcome difficulties in a person, to put the target and go to her. These qualities are indispensable in everyday life, they contribute to the development of a person and personality.

Physical development is a direct indicator of public health.

Physical development- These are the properties of the body, allowing to determine the age characteristics, a stock of physical forces and endurance.

The formation of physical development is influenced by a number of antico-biological factors (gender, age, constitution, heredity, etc.);

Natural climatic (temperature, humidity, landscape);

Socio-economic (level of economic development of society, working conditions and life, material and cultural levels, etc.).

Physical development data is used to assess the effectiveness of sanitary and hygienic, preventive and wellness activities.

Indicators of physical development are used to identify anthropometric risk markers of diseases. Some anthropometric indicators are the most important criteria for determining such concepts as "live births", "stillbirth", "prematurity", etc. Indicators of physical development are necessary to standardize clothing, shoes, furniture, rational device of workplaces, etc.

Disorders of physical development indicate adverse conditions of lifestyle, which requires medical and social impact measures.

Control over physical development is one of the essential elements of the daily activities of medical workers. Therefore, the Middle Medical Worker must own the methods of studying physical development, know the basic rules of its assessment.

In the study of morphological and functional signs characterizing physical development, the anthropometry method is used (from Greek. Antropos - man and Metreo - measure). Anthropometry allows you to quantify the variation of the physical properties of a person. When studying physical development, an integrated approach is used, based on such indicators as:

1) Somatometric (morphological), are determined by measuring the size of the body and its parts: the length and weight of the body, the body length is sitting, the trigger of the chest;

2) physiometric (functional), are determined with the Special Physical Instruments: Life Capacity

lungs (jerking), chest excursion, muscle strength hands, milling force;

3) Somatoscopic (descriptive) based on body description in general or individual parts: the state of the musculoskeletal system (posture, the form of the chest), the elasticity of the skin, the development of muscles, the degree of grease, the type of physique, as well as the biological level of body development ( The degree of development of secondary sexual signs, the number of constant teeth and the order of their teething, etc.).

Observation of the physical development of the population is a mandatory component of a health control system for health. It is systematic.

Physical development control begins with the moment of human birth. The first anthropometric measurements are carried out in the maternity hospital. This work continues in children's clinics and children's preschool institutions, during in-depth medical examinations in schools. Based on the developed age and sexual standards of the physical development of homogeneous ethnic groups, group and individual assessments of the level of physical development of schoolchildren and correction as they need their physical development are carried out.

The role of the physical development of young people is especially great. It is during this period that it is possible to carry out directional changes in the morphology of the organism - forms, sizes and proportions of the body. The assessment of physical development is carried out among students of secondary and higher educational institutions, when calling to the army and during military service. The observations of the physical development of the adult population are carried out with in-depth periodic medical examinations of various groups of the population - workers industrial enterprises, students, athletes, etc.

Data on the physical development obtained in the process of current medical observation is recorded in medical documents (the history of the child's development, the medical card of the outpatient patient, the medical record of the recruitment, the medical record of the serviceman, etc.).

For an in-depth study of the physical development of children, adolescents and adults, special accounting and statistical documents can be developed. Statistical data development, analysis and group assessment of physical development are carried out using medical statistics.

The study of physical development consists of:

1) assess the physical development of various age-genital groups;

2) dynamic monitoring of physical development in the same groups;

3) developing age-sex standards of physical development of children;

4) Evaluation of the effectiveness of health events on
The basis of shifts in a state of physical development.

To study, analyzing and assessing the physical development of the population, generalizing and individualizing observation methods are used.

The generalizing method involves monitoring a sufficiently large group of children in which individual anthropometric data is summed up. When processing the results of the study, the average physical development indicators at a certain point in time are obtained.

Individualizing method is a long monitoring of the development of each child.

To obtain average physical development indicators, there are examination of large groups of practically healthy people of certain age and gender. The averages obtained are the standards of the physical development of the relevant groups of the population. Generally accepted standards does not exist. Various levels of living in different climate-geographical zones, cities and countryside, ethnographic differences cause different levels of physical development of the population. In accordance with this, regional standards are determined.

Evaluation of physical development is carried out when comparing individual indicators with standards. For this purpose, the method of sigmal deviations is used. The essence of it is that the physical development indicators of the individual compared with standard data for the appropriate age-sex group and calculate the magnitude of the sigmal deflection, with which the degree of physical development is determined. It can be defined as the average, above or below average, high or low. When using this method, all signs of physical development are estimated in isolated.

The more complete assessment of the signs of physical development of the individual allows us to obtain a method for evaluating the regression scales. Using the regression scale, you can determine the degree of physical development for the aggregate of morphological signs (body length, body weight, chest circumference). This method makes it possible to identify persons with harmonious and disharmonic development, but does not allow to take into account the level of biological development of an individual.

In recent years, a core method of assessing the state of physical development has been widespread. This method is the most strict and objective. Central tables show quantitative data of physical development in children of specific age and gender.

Acceleration(from Lat. Acceleratio - acceleration) - acceleration of growth and development of children and adolescents compared to previous generations. This concept was introduced in 1935 by the German physician E. Koh. The most clearly acceleration manifested itself in the second half of the XX century. It is noted an increase in the length and mass of the body of newborns. In the children of the first year of life, it was expressed in large growth parameters, earlier incessing the spring, in the 6-7-year-old age - in the early change of dairy teeth for permanent. Changing the pace of age development of school children's children is based mainly on the development of secondary sexual signs, early sexual ripening, acceleration of the skeletonasification processes. Currently, the process of ossification ends at boys to 2, and girls - for 3 years earlier than in the 30s. Acceleration is also manifested in changing a number of functional indicators (early establishment of heart rate and blood pressure values \u200b\u200bat levels characteristic of adults).

There are various hypotheses for the causes of acceleration shifts. The first group includes physico-chemical hypothesis, according to which the acceleration is a consequence of intensive insolation, the effects of electromagnetic waves, radiation changes. The second group constitutes hypotheses, whose supporters explain the acceleration by the influence of changing living conditions and, first of all, improving the nutrition of children (an increase in the consumption of animal proteins and fats, vitamins, high-calorie concentrates for breastfeeding). A number of scientists adhere to the hypotheses of urbanization, believing that the accelerated pace of urban life, the active impact of the media (television, radio, cinema, computer means of communication) render an exciting effect on the central nervous system and activate its trop functions. According to the genetic theory, as a result of active mixing of the population of the planet, heterogeneity increases in various populations due to the increase in mixed marriages between previously isolated groups of people, which leads to the acceleration of the development of children.

However, none of these hypotheses (theories) cannot claim an exhaustive rationale for acceleration. Therefore, most researchers consider accelerating the growth and development of the younger generation as a result of the complex interaction of ex- and endogenous, biological and social factors.

Acceleration shifts are periodic with short-term stabilization periods. Scientists predict the slowdown in acceleration in economically developed countries in the coming decades. However, in developing countries in Asia, Africa and Latin America, a significant acceleration of the individual development of children is expected.

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Physical development

Physical development - This is the process of becoming the formation, formation and subsequent change throughout the life of the individual of the morphofunctional properties of its organism and physical qualities based on them and abilities.

Physical development Characterized by changes in three groups of indicators.

1. Telecommunication indicators (body length, body weight, posture, volumes and shapes of individual body parts, weight of grease, etc.), which are primarily biological forms, or morphology, humans.

2. Indicators (criteria) of health, reflecting morphological and functional changes in human physiological systems. The functioning of cardiovascular, respiratory and central nervous systems, digestive organs, and the mechanisms of thermoregulation, etc. has crucial importance on human health.

3. Indicators of the development of physical qualities (forces, high-speed abilities, endurance, etc.).

Approximately 25 years old (period of formation and growth) Most morphological indicators increase in size and improved the functions of the body. Then, up to 45-50 years, physical development as it were stabilized at a certain level. In the future, as agreed, the functional activity of the body gradually weakens and worsens, the length of the body, muscle mass, etc. can be reduced.

Physical development to a certain extent determined inheritance laws,which should be taken into account as factors conducive or, on the contrary, impeding the physical improvement of a person. Inheritance, in particular, should be taken into account when predicting the possibilities and success of a person in sports.

The process of physical development obeys also the law of age-related speed.It is possible to intervene in the process of physical development of a person for the purpose of management, it is possible only on the basis of accounting for the features and capabilities of the human body in various age periods: during the period of becoming and growth, during the highest development of its forms and functions during the aging period.

The process of physical development obeys the law of unity of the body and environmentand, therefore, it significantly depends on the living conditions of a person. The conditions of life are primarily among social conditions. The conditions for life, labor, upbringing and material support are largely affected by the physical condition of the person and determine the development and change in the forms and functions of the body. A well-known influence on physical development also has a geographical environment.

Of great importance for managing physical development in the process of physical education have biological law exerciseand the law of unity of forms and functionsthe body in its activities. These laws are shipped when choosing funds and methods of physical education in each case.

Choosing physical exercises and determining the magnitude of their loads, according to law of exercise You can count on the necessary adaptation restructuring in the body of engaged. It takes into account that the body functions as a whole. Therefore, selecting exercises and loads, mostly electoral impact, it is necessary to clearly imagine all sides of their influence on the body.