Local effect of increasing fitness. General and local effects of physical exercise (load) on the human body

Local effect increasing fitness, which is an integral part of the general, is associated with an increase in the functionality of individual physiological systems.

Changes in the composition of the blood. The regulation of blood composition depends on a number of factors that can be influenced by a person: good nutrition, exposure to fresh air, regular physical activity, etc. In this context, we consider the effect of physical activity. With regular physical exercise, the number of red blood cells increases in the blood (during short-term intensive work - due to the release of red blood cells from the "blood depots"; with prolonged intense exercise - due to increased functions of the hematopoietic organs). The content of hemoglobin per unit volume of blood increases, respectively, the oxygen capacity of the blood increases, which enhances its oxygen-transport capability.

At the same time, an increase in the content of leukocytes and their activity is observed in the circulating blood. Special studies have found that regular physical training without overload increases the phagocytic activity of blood components, i.e. increases the body's nonspecific resistance to various adverse, especially infectious, factors.

Rice. 4.2

The work of the heart at rest (according to V.K. Dobrovolsky)

A person's fitness also contributes to a better transfer of the concentration of lactic acid in the arterial blood that increases during muscular work. In untrained people, the maximum allowable concentration of lactic acid in the blood is 100-150 mg%, and in trained people it can increase up to 250 mg%, which indicates their great potential to perform maximum physical exertion. All these changes in the blood of a physically trained person are considered favorable not only for performing intense muscular work, but also for maintaining a general active life.

Changes in the work of the cardiovascular

Heart. Before talking about the effect of physical activity on the central organ of the cardiovascular system, one must at least imagine the enormous work that it does even at rest (see Fig. 4.2). Under the influence of physical activity, the boundaries of its capabilities expand, and it adapts to the transfer of much more blood than the heart of an untrained person can do (see Fig. 4.3). Working with an increased load during active physical exercises, the heart inevitably trains itself, since in this case, through the coronary vessels, the nutrition of the heart muscle itself improves, its mass increases, its size and functionality change.

Indicators of heart performance are pulse rate, blood pressure, systolic blood volume, minute volume of blood. The simplest and most informative indicator of the work of the cardiovascular system is the pulse.

Pulse - a wave of oscillations propagating along the elastic walls of the arteries as a result of the hydrodynamic impact of a portion of blood ejected

Rice. 4.3. The work of the heart during the passage

100 km distance skier

(according to V.K. Dobrovolsky)

15 l of blood in 1 min 100 ml of blood in 1 beat Pulse 150 beats/min

15 l of blood in 1 min 150 ml of blood in 1 beat. Pulse 100 beats/min

Rice. 4.4. The change in heart rate during a test on a bicycle ergometer with the same intensity of work provides valuable information about the efficiency of the heart. With the same work, a trained person has a lower heart rate than an untrained one. This indicates that the training led to an increase in the strength of the heart muscle and, thereby, in the stroke volume of the blood.

(according to R. Hedman)

into the aorta under high pressure with the contraction of the left ventricle. The pulse rate corresponds to the heart rate (HR) and averages 60-80 beats / min. Regular physical activity causes a decrease in heart rate at rest due to an increase in the rest (relaxation) phase of the heart muscle (see Fig. 4.4). The maximum heart rate in trained people during physical activity is at the level of 200-220 beats / min. An untrained heart cannot reach such a frequency, which limits its capabilities in stressful situations.

Blood pressure (BP) is created by the force of contraction of the ventricles of the heart and the elasticity of the walls of the vessels. It is measured in the brachial artery. Distinguish between the maximum (systolic) pressure, which is created during the contraction of the left ventricle (systole), and the minimum (diastolic) pressure, which is noted during the relaxation of the left ventricle (diastole). Normally, a healthy person aged 18-40 at rest has a blood pressure of 120/80 mm Hg. Art. (for women, 5-10 mm lower). During physical exertion, the maximum pressure can increase up to 200 mm Hg. Art. and more. After the termination of the load in trained people, it quickly recovers, while in untrained people it remains elevated for a long time, and if intensive work continues, a pathological condition may occur.

The systolic volume at rest, which is largely determined by the force of contraction of the heart muscle, in an untrained person is 50-70 ml, in a trained person - 70-80 ml, and with a rarer pulse. With intensive muscular work, it ranges from 100 to 200 ml or more, respectively (depending on age and fitness). The greatest systolic volume is observed at a pulse of 130 to 180 beats/min, while at a pulse above 180 beats/min it begins to decrease significantly. Therefore, to increase the fitness of the heart and the overall endurance of a person, physical activity at a heart rate of 130-180 beats / min is considered the most optimal.

Blood vessels, as already noted, provide a constant movement of blood in the body under the influence of not only the work of the heart, but also the pressure difference in the arteries and veins. This difference increases with increasing activity of movements. Physical work contributes to the expansion of blood vessels, reducing the constant tone of their walls, increasing their elasticity.

Promotion of blood in the vessels is also facilitated by the alternation of tension and relaxation of actively working skeletal muscles (“muscle pump”). With active motor activity, there is a positive effect on the walls of large arteries, the muscle tissue of which tenses and relaxes with great frequency. During physical exertion, the microscopic capillary network is almost completely opened, which at rest is only 30-40% active. All this allows you to significantly speed up blood flow.

So, if at rest the blood makes a complete circulation in 21-22 s, then during physical exertion - in 8 s or less. At the same time, the volume of circulating blood can increase up to 40 l / min, which greatly increases blood supply, and, consequently, the supply of nutrients and oxygen to all cells and tissues of the body.

At the same time, it has been established that prolonged and intense mental work, as well as a state of neuro-emotional stress, can significantly increase the heart rate to 100 beats / min or more. But at the same time, as noted in Chap. 3, the vascular bed does not expand, as it happens during physical work, but narrows (!). Increases, but does not decrease (!) Also the tone of the walls of blood vessels. Even spasms are possible. Such a reaction is especially characteristic of the vessels of the heart and brain.

Thus, long-term intense mental work, neuro-emotional states that are not balanced with active movements, with physical exertion, can lead to a deterioration in the blood supply to the heart and brain, other vital organs, to a persistent increase in blood pressure, to the formation of a “fashionable” nowadays among students disease - vegetative-vascular dystonia.

Changes in the respiratory system

The work of the respiratory system (together with blood circulation) in terms of gas exchange, which increases with muscle activity, is assessed by respiratory rate, pulmonary ventilation, lung capacity, oxygen consumption, oxygen debt and other indicators. At the same time, it should be remembered that there are special mechanisms in the body that automatically control breathing. Even in an unconscious state, the breathing process does not stop. The main regulator of respiration is the respiratory center located in the medulla oblongata.

At rest, breathing is performed rhythmically, and the time ratio of inhalation and exhalation is approximately 1:2. When performing work, the frequency and rhythm of breathing can change depending on the rhythm of movement. But in practice, a person's breathing can be different depending on the situation. At the same time, he can consciously control his breathing to some extent: delay, change in frequency and depth, i.e. change its individual parameters.

The respiratory rate (change of inhalation and exhalation and respiratory pause) at rest is 16-20 cycles. During physical work, the respiratory rate increases by an average of 2-4 times. With an increase in breathing, its depth inevitably decreases, and individual indicators of breathing efficiency also change. This is especially clearly seen in trained athletes (see Table 4.1).

It is no coincidence that in competitive practice in cyclic sports, a respiratory rate of 40-80 per minute is observed, which provides the highest oxygen consumption.

Strength and static exercises are widespread in sports. Their duration is insignificant: from tenths of a second to 1-3 s - a blow in boxing, the final effort in throwing, holding positions in gymnastics, etc .; from 3 to 8 s - barbell, handstand

When performing standard muscular work equal to that of untrained, trained athletes expend less energy and perform work with high efficiency. The magnitude of the shifts in their physiological functions is insignificant.

The effect of increasing economization when performing standard work of moderate power, it is clearly manifested in young athletes.

After performing a standard physical load, trained athletes have a quick recovery of working capacity. The growth of fitness is accompanied by optimization in the ratio of motor and vegetative components of motor skills. Thus, in high-class runners, the ratio of heart rate to the frequency of running steps approaches one. For athletes of the lower ranks, it ranges from 1.1 to 1.3.

In the state of acid-base balance after standard test loads (five-minute run, standard bicycle ergometric test) in trained athletes, blood pH shifts are insignificant (from 7.36 to 7.32-7.30). In untrained athletes, the drop in alkaline reserve is more pronounced: pH changes to 7.25 - 7.2. Restoration of indicators of acid-base balance is delayed in time.

The most characteristic feature in the change in physiological functions in trained athletes when performing extremely intense muscular work is the maximum mobilization of the body's functional resources.

"Human Physiology", N.A. Fomin

The potential ability of an athlete to perform physical activity can, to a certain extent, be judged by the indicators of physiological functions in a state of relative muscle rest or when performing work that allows predicting performance at a given value (for example, according to the PWC-170 test, which characterizes the power of work at a pulse rate of 170 beats/min). A high level of fitness in a state of relative muscle rest is characterized by functional ...

Energy metabolism in a state of relative muscle rest in athletes is, as a rule, at the level of standard values. There are, however, cases of both lowering and increasing it compared to standard values. In terms of the functions of the cardiovascular and respiratory systems, the effect of the economizing effect of training is clearly manifested. Due to the increase in parasympathetic influences, the frequency of pulse and respiration, shock and ...

Cases of the so-called sports anemia of the fall - hemoglobin content up to 13 - 14% - with a simultaneous increase in blood plasma volume - are a rare exception. This is observed after the performance of inadequate loads by young athletes. Increasing the amount of protein in the diet, taking vitamin B12, folic acid, and iron supplements prevent the onset of sports anemia. The central nervous system is characterized by...

Physiological mechanisms of the prelaunch state. Prior to the start of muscular activity in the body of an athlete, there are noticeable shifts in the functions of individual organs and systems. They depend on how difficult the upcoming muscular work is, as well as on the scale and responsibility of the upcoming competition. The complex of changes in physiological and mental functions that occurs before the start of an athlete's performance in competitions is called the pre-launch state. Distinguish between early...

The body of each person has certain reserve capabilities in resisting the influences of the external environment. The ability to perform various types of physical work can increase many times, but up to a certain limit. Regular muscle activity (training) by improving physiological mechanisms mobilizes the available reserves, pushing their limits.

Overall positive effect

The overall effect of regular exercise (training) is to:

Increasing the stability of the central nervous system: at rest, trained individuals have a slightly lower excitability of the nervous system; during work, the possibility of achieving increased excitability increases and the lability of the peripheral nervous system increases;

Positive changes in the musculoskeletal system: the mass and volume of skeletal muscles increase, their blood supply improves, tendons and ligaments of the joints become stronger, etc .;

Economization of the functions of individual organs and blood circulation in general; in improving the composition of the blood, etc.;

Reducing energy consumption at rest: due to the economization of all functions, the total energy consumption of a trained organism is lower than that of an untrained one by 10–15%;

A significant reduction in the recovery period after physical activity of any intensity.

As a rule, an increase in general fitness for physical activity also has a non-specific effect - an increase in the body's resistance to the action of adverse environmental factors (stressful situations, high and low temperatures, radiation, injuries, hypoxia), to colds and infectious diseases.

At the same time, long-term use of extreme training loads, which is especially common in "big sports", can lead to the opposite effect - immunosuppression and increased susceptibility to infectious diseases.

Local effect of physical activity

The local effect of increasing fitness, which is an integral part of the general effect, is associated with an increase in the functionality of individual physiological systems.

Changes in the composition of the blood. The regulation of blood composition depends on a number of factors that can be influenced by a person: good nutrition, exposure to fresh air, regular physical activity, etc. In this context, we consider the effect of physical activity. With regular physical exercises, the number of red blood cells increases in the blood (during short-term intensive work - due to the release of red blood cells from the "blood depots"; with prolonged intense exercise - due to increased functions of the hematopoietic organs). The content of hemoglobin per unit volume of blood increases, respectively, the oxygen capacity of the blood increases, which enhances its oxygen-transport capability.

At the same time, an increase in the content of leukocytes and their activity are observed in the circulating blood. Special studies have found that regular physical training without overload increases the phagocytic activity of blood components, i.e. increases the body's nonspecific resistance to various adverse, especially infectious, factors.

A person's training contributes to a better transfer of the concentration of lactic acid in the arterial blood that increases during muscular work. In untrained people, the maximum allowable concentration of lactic acid in the blood is 100–150 mg%, and in trained people it can increase.

up to 250 mg%, which indicates their great potential to perform maximum physical activity. All these changes in the blood of a physically trained person are considered favorable not only for performing intense muscular work, but also for maintaining a general active life.

Changes in the work of the cardiovascular system

Heart. Even at rest, the heart does a great job. Under the influence of physical activity, the boundaries of its capabilities expand, and it adapts to the transfer of much more blood than the heart of an untrained person can do. Working with an increased load during active physical exercises, the heart inevitably trains itself, since in this case, through the coronary vessels, the nutrition of the heart muscle itself improves, its mass increases, its size and functionality change.

Pulse- a wave of oscillations propagating along the elastic walls of the arteries as a result of the hydrodynamic impact of a portion of blood ejected into the aorta under high pressure during the contraction of the left ventricle. The pulse rate corresponds to the heart rate (HR) and averages

60–80 beats/min. Regular physical activity causes a decrease in heart rate at rest by increasing the rest (relaxation) phase of the heart muscle. The maximum heart rate in trained people during physical activity is at the level of 200–220 beats / min. An untrained heart cannot reach such a frequency, which limits its capabilities in stressful situations.

Arterial pressure (BP) is created by the force of contraction of the ventricles of the heart and the elasticity of the walls of blood vessels. It is measured in the brachial artery. Distinguish between the maximum (systolic) pressure, which is created during the contraction of the left ventricle (systole), and the minimum (diastolic) pressure, which is noted during the relaxation of the left ventricle (diastole). Normally, a healthy person aged 18–40 years at rest has a blood pressure of 120/80 mm Hg. Art. (for women, 5–10 mm lower). During physical exertion, the maximum pressure can increase up to 200 mm Hg. Art. and more. After the termination of the load in trained people, it quickly recovers, while in untrained people it remains elevated for a long time, and if intensive work continues, a pathological condition may occur.

The systolic volume at rest, which is largely determined by the force of contraction of the heart muscle, in an untrained person is 50-70 ml, in a trained person - 70-80 ml, and with a slower pulse. With intensive muscular work, it ranges from 100 to 200 ml or more, respectively (depending on age and fitness). The greatest systolic volume is observed at a pulse of 130 to 180 beats/min, while at a pulse above 180 beats/min it begins to decrease significantly. Therefore, to increase the fitness of the heart and the general endurance of a person, physical activity at a heart rate of

130–180 beats/min.

Promotion of blood in the vessels is also facilitated by the alternation of tension and relaxation of actively working skeletal muscles (“muscle pump”). With active motor activity, there is a positive effect on the walls of large arteries, the muscle tissue of which tenses and relaxes with great frequency. During physical exertion, the microscopic capillary network is almost completely opened, which at rest is only 30–40% active. All this allows you to significantly speed up blood flow.

So, if at rest the blood makes a complete circulation in 21–22 s, then during physical exertion it takes 8 s or less. At the same time, the volume of circulating blood can increase up to 40 l / min, which greatly increases blood supply, and, consequently, the supply of nutrients and oxygen to all cells and tissues of the body.

At the same time, it has been established that prolonged and intense mental work, as well as a state of neuro-emotional stress, can significantly increase the heart rate to 100 beats/min or more. Thus, long-term intense mental work, neuro-emotional states that are not balanced with active movements, with physical exertion, can lead to a deterioration in the blood supply to the heart and brain, other vital organs, to a persistent increase in blood pressure, to the formation of a “fashionable” nowadays among students of the disease - vegetative-vascular dystonia.

Changes in the respiratory system

The respiratory rate (change of inhalation and exhalation and respiratory pause) at rest is 16–20 cycles. During physical work, the respiratory rate increases by an average of 2-4 times. With an increase in breathing, its depth inevitably decreases, and individual indicators of breathing efficiency also change. This is especially clearly seen in trained athletes (Table 3).

In competitive practice in cyclic sports, a respiratory rate of 40–80 cycles per minute is observed, which provides the highest oxygen consumption.

Strength and static exercises are widespread in sports. Their duration is insignificant: from tenths of a second to 1-3 s - a blow in boxing, the final effort in throwing, holding postures in gymnastics, etc .; from 3 to 8 s - barbell, handstand, etc.; from 10 to 20 s - shooting, keeping the opponent on the "bridge" in the fight, etc.

Table 3

Indicators of the respiratory system at different respiratory rates in the master of sports in cycling (in the experiment) (according to V.V. Mikhailov)

Table 4

Weight lifting by subjects in different phases of breathing

(according to V.V. Mikhailov)

From a sports point of view, it is more expedient to perform these exercises and movements while holding the breath or exhaling (Table 4), the greatest effort develops during holding the breath (although this is unfavorable for health).

Tidal volume- the amount of air passing through the lungs during one respiratory cycle (inhalation, respiratory pause, exhalation). The value of the respiratory volume is directly dependent on the degree of fitness for physical activity. At rest, in untrained people, the tidal volume is 350–500 ml, in trained people, 800 ml or more. With intensive physical work, it can increase to about 2500 ml.

Pulmonary ventilation- the volume of air that passes through the lungs in 1 minute. The value of pulmonary ventilation is determined by multiplying the value of the tidal volume by the respiratory rate. Pulmonary ventilation at rest is 5-9 liters. Its maximum value in untrained people is up to 150 liters, and in athletes it reaches 250 liters.

Vital capacity (VC)- the largest volume of air that a person can exhale after the deepest breath. For different people, the vital capacity is not the same. Its value depends on the age, weight and length of the body, gender, the state of physical fitness of a person and other factors. VC is determined using a spirometer. Its average value is 3000 - 3500 ml for women, 3800 - 4200 ml for men. In people involved in physical culture, it increases significantly and reaches in women

5000 ml, for men - 7000 ml or more.

Oxygen consumption- the amount of oxygen actually used by the body at rest or when performing any work in 1 minute.

Maximum Oxygen Consumption (MPC)- the maximum amount of oxygen that the body can absorb during extremely difficult work for it. BMD is an important criterion for the functional state of the respiratory and circulatory systems.

MPC is an indicator of the aerobic (oxygen) performance of the body, i.e. its ability to perform intense physical work with sufficient oxygen entering the body to obtain the necessary energy. MIC has a limit, which depends on age, the state of the cardiovascular and respiratory systems, on the activity of metabolic processes and is directly dependent on the degree of physical fitness.

For those who do not play sports, the MIC limit is at the level

2 - 3.5 l/min. In high-class athletes, especially those involved in cyclic sports, the IPC can reach: in women - 4 l / min and more; in men - 6 l / min or more. With an orientation to the IPC, an assessment of the intensity of physical activity is also given. So, the intensity below 50% of the IPC is regarded as mild, 50 - 75% of the IPC is moderate, over 75% of the IPC is considered severe.

oxygen debt- the amount of oxygen necessary for the oxidation of metabolic products accumulated during physical work. With prolonged intensive work, a total oxygen debt arises, the maximum possible value of which for each person has a limit (ceiling). Oxygen debt is formed when the oxygen demand of the human body is higher than the oxygen consumption ceiling at the moment. For example, when running for 5000 m, the oxygen demand of an athlete who overcomes this distance in 14 minutes is 7 liters per 1 minute, and the consumption ceiling for this athlete is 5.3 liters, therefore, an oxygen debt equal to 1 occurs in the body every minute. .7 l.

Untrained people are able to continue working with a debt not exceeding 6-10 liters. High-class athletes (especially in cyclic sports) can perform such a load, after which there is an oxygen debt of 16-18 liters or even more. Oxygen debt is liquidated after the end of work. The time of its elimination depends on the duration and intensity of work (from several minutes to 1.5 hours).

The listed indicators of the capacity of the cardiovascular system (CVS) and respiratory function and its components are especially significant in swimmers, skiers, runners for medium and long distances.

Oxygen starvation of the body–hypoxia. When less oxygen enters the tissue cells than is necessary to fully ensure energy consumption (i.e., oxygen debt), oxygen starvation, or hypoxia, occurs. It can occur not only because of oxygen debt during physical exertion of increased intensity. Hypoxia can occur for other reasons, both external and internal.

Table 5

Differences in the reserve capabilities of the body in an untrained person and an athlete (according to I.V. Muravov)

Index

untrained person

B-A ratio

Athlete

B-A ratio

at rest A

after maximum load B

The cardiovascular system

Heart rate per minute

2,0

Systolic blood volume

0,5

2,8

Minute blood volume (l)

2,6

4,5

Respiratory system

Respiratory rate (per minute)

16-18

1,8

Tidal volume (ml)

2,0

8,5

Minute ventilation (l)

4,5

33,3

Oxygen consumption in 1 min (ml)

33,3

excretory system

Perspiration through the skin (ml)

External causes include air pollution, and climbing to a height (in the mountains, flying in an airplane), etc. In these cases, the partial pressure of oxygen in the atmospheric and alveolar air drops and the amount of oxygen entering the blood to deliver it to the tissues decreases.

If at sea level the partial pressure of oxygen in atmospheric air is 159 mm Hg. Art., then at an altitude of 3000 m it decreases to 110 mm, and at an altitude of 5000 m to 75–80 mm Hg.

The internal causes of hypoxia depend on the state of the respiratory apparatus and the cardiovascular system of the human body. Hypoxia, due to internal causes, also occurs with a chronic lack of movement (hypokinesia), and with mental fatigue, as well as with various diseases.

In table. 5 shows the reserve capacity of trained and untrained people in terms of the most important physiological indicators.

Changes in the musculoskeletal and other body systems during physical activity

Regular physical activity increases the strength of bone tissue, increases the elasticity of muscle tendons and ligaments, and increases the production of intra-articular (synovial) fluid. All this contributes to an increase in the amplitude of movements (flexibility). Noticeable changes also occur in skeletal muscles. Due to the increase in the number and thickening of muscle fibers, an increase in muscle strength indicators occurs. In athletes and those who do not exercise, they differ significantly (Table 6). Similar differences are also achieved by improving the neuro-coordination support of muscle work - the ability to simultaneously participate in a separate movement of the maximum number of muscle fibers and to completely and simultaneously relax them. With regular physical activity, the body's ability to store carbohydrates in the form of glycogen in the muscles (and liver) increases and thereby improves the so-called tissue respiration of the muscles. If on average the value of this reserve is 350 g for an untrained person, then for an athlete it can reach 500 g. This increases his potential for the manifestation of not only physical, but also mental performance.

Table 6

Average indicators of muscles - flexors of the hand of the strongest arm

The life activity of the organism is based on the process of automatic maintenance of vital factors at the required level, any deviation from which leads to the immediate mobilization of the mechanism that restores this level (homeostasis).

Homeostasis is a set of reactions that ensure the maintenance or restoration of a relatively dynamic constancy of the internal environment and some physiological functions of the human body (blood circulation, metabolism, thermoregulation, etc.). Next, consider the structure of the human body.

An organism is a single, integral, complex self-regulating living system, consisting of organs and tissues. Organs are built from tissues, tissues are made up of cells and intercellular substance.

The skeletal system and its functions. It is customary to distinguish the following physiological systems of organisms: bone (human skeleton), muscle, circulatory, respiratory, digestive, nervous, blood system, endocrine glands, analyzers, etc.

The chest is formed by 12 thoracic vertebrae, 12 pairs of ribs and the sternum (sternum), it protects the heart, lungs, liver and part of the digestive tract; the volume of the chest can change during breathing with the contraction of the intercostal muscles and the diaphragm.

The skull protects the brain and sensory centers from external influences. It consists of 20 paired and unpaired bones, connected to each other motionlessly, except for the lower jaw. The skull is connected to the spine with the help of two condyles of the occipital bone with the upper cervical vertebrae, which have corresponding articular surfaces.

The skeleton of the upper limb is formed by the shoulder girdle, consisting of 2 shoulder blades and 2 clavicles, and the free upper limb, including the shoulder, forearm and hand. The shoulder is 1 humeral tubular bone; the forearm is formed by the radius and ulna; the skeleton of the hand is divided into the wrist (8 bones arranged in 2 rows), the metacarpus (5 short tubular bones) and the phalanges of the fingers (14 phalanges).

The skeleton of the lower limb is formed by the pelvic girdle (2 pelvic bones and the sacrum) and the skeleton of the free lower limb, which consists of 3 main sections - the thigh (1 femur), the lower leg (tibia and fibula) and the foot (tarsus-7 bones, metatarsus -5 bones and 14 phalanges).

All bones of the skeleton are connected through joints, ligaments and tendons.

Joints are movable joints, the area of contact of the bones in which is covered with an articular bag of dense connective tissue, fused with the periosteum of the articulating bones. The joint cavity is hermetically sealed, it has a small volume, depending on the shape and size of the joints.

Muscular system and its function. There are 2 types of muscles: smooth (involuntary) and striated (voluntary). Smooth muscles are located in the walls of blood vessels and some internal organs. They constrict or dilate blood vessels, move food through the gastrointestinal tract, and contract the walls of the bladder. Striated muscles are all skeletal muscles that provide a variety of body movements. The striated muscles also include the heart muscle, which automatically ensures the rhythmic work of the heart throughout life. The basis of muscles is proteins, which make up 80-85% of muscle tissue (excluding water). The main property of muscle tissue is contractility, it is provided due to contractile muscle proteins - actin and myosin.

The muscles of the trunk include the muscles of the chest, back and abdomen.

Receptors and analyzers. Human receptors are divided into two main groups: extero- (external) and intero- (internal) receptors. Each such receptor is an integral part of the analyzing system, which is called the analyzer. The analyzer consists of three sections - the receptor, the conductive part and the central formation in the brain.

The highest department of the analyzer is the cortical department. Let us list the names of the analyzers, the role of which in human life is known to many.

Endocrine system. Endocrine glands, or endocrine glands, produce special biological substances - hormones. The endocrine glands include: thyroid, parathyroid, goiter, adrenal glands, pancreas, pituitary gland, gonads and a number of others.

The natural age-related physical development of a person is the basic basis for his perfection.

About 20-22 years pass from the birth of a person to his biological maturation. During this long time, complex processes of morphological, physical and psychological development take place. The first two processes are combined into the concept of "physical development".

Physical development is a regular natural process of formation and change in the morphological and functional properties of the body in the course of individual life. The criteria for physical development are mainly the main anthropometric (macromorphological) indicators: body length (height), body weight (weight), girth, perimeter (circumference) of the chest.

Natural physical development is also associated with the age dynamics of a number of functional indicators. In this regard, when assessing physical development, the degree of correspondence between the development of basic motor qualities (dexterity, speed, flexibility, strength, endurance) to average age indicators is most often taken into account.

The dynamics of the physical development of an individual is closely related to his individual age characteristics, which are more or less influenced by heredity.

Constantly changing environmental conditions - domestic, educational, labor, environmental, etc. - can have a positive or negative impact on physical development. But it is very important that a number of indicators of a person's physical development throughout his life can be subjected to directed influence correction or improvement through active physical exercise.

Age-related changes in body length (height)

Body length differs significantly between men and women. It has a fairly stable hereditary character from parents, although manifestations of heredity from older generations are often observed.

On average, at the age of 18–25 years (earlier in women, later in men), the final ossification of the skeleton occurs and the growth of the body in length is completed. Individual deviations in time in this process are often significant. This may be due to temporary or permanent endocrine disorders, various functional loads, living conditions, etc.

The degree and conditions of the influence of heredity on the physical development and life of a person.

The whole complex of the formation of morphological functional indicators of human physical development is due to internal factors and external conditions. An essential internal factor is the genetically incorporated program of heredity. However, heredity in its structure is not unambiguous. There are hereditary factors, clearly expressed (sometimes pathological), and factors of the "predisposition" of the individual's body to certain deviations in the normal development of its natural morphological or functional properties. The latter can manifest themselves in the long-term process of formation and life activity only under certain regimes and under specific conditions of the influence of the external environment. However, even in this case it is impossible to speak about the fatality of the manifestation of this heredity.

The tasks and possibilities of physical culture are precisely to increase the body's resistance to negative factors through regular exercise, targeted selection of physical exercises and the use of other means of physical culture. Thus, it is possible to prevent the manifestation of a negative hereditary predisposition by turning on the compensatory mechanisms of the body.

So, for example, genetically incorporated heredity, manifested in a reduced content of hemoglobin in the blood, can be compensated to a certain extent by the fitness of the cardiovascular and respiratory systems while providing the body with oxygen. There are many such examples.

Physical culture is able to solve such problems in the process of physical education independently or in conjunction with medical measures through the treatment of movements (kinesiotherapy) in therapeutic physical culture (LFK).

We emphasize once again that not in all cases, negative heredity is fatal. It can be fought, including by means of physical culture.

The influence of natural and climatic factors on human life

The climate has a direct and indirect effect on a person. The direct influence is very diverse and is due to the direct action of climatic factors on the human body and, above all, on the conditions of its heat exchange with the environment: on the blood supply to the skin, respiratory, cardiovascular and sweating systems.

Most of the physical factors of the environment, in interaction with which the human body has evolved, are of an electromagnetic nature.

Among climatic factors, the short-wave part of the solar spectrum, ultraviolet radiation (UVR) (wavelength 295–400 nm), is of great biological importance.

Temperature is one of the important abiotic factors affecting all physiological functions of all living organisms.

The influence of environmental factors on human life.

All environmental factors act on living organisms in different ways. Some of them provide them with life, others harm them, and others may be indifferent to them. Environmental factors that affect the body in one way or another are called environmental factors. According to the origin and nature of the impact, environmental factors are divided into abiotic, biotic and anthropic.

Violation of the natural balance leads to imbalance of the integral system "man - environment". Pollution of air, water, soil, food, noise loads, stressful situations as a result of an accelerated rhythm of life, negatively affect human health, both physical and mental.

The problem of the relationship between man and nature, harmony between society and the environment has always been relevant. Most gerontologists (scientists who work on the problem of longevity), biologists, ecologists and clinicians believe that the human body can and should function normally for more than 100 years. The health, biological and moral perfection of each person largely depends on the state of the social and natural environment of his life. The complex influence of vital components should form optimal ecological conditions for human existence.

The biological future of mankind depends, first of all, on how much it manages to preserve the main natural parameters that ensure a full life - a certain gas composition of the atmosphere, the purity of fresh and sea water, soil, flora and fauna, a favorable thermal regime in the biosphere, low radiation background on the ground.

The influence of purely social factors on human life.

Currently, emissions and waste from industrial enterprises and human activities often cause irreparable damage to nature and humans. Pollution of the atmosphere, soil, groundwater, increased radiation - all this creates harsh conditions for the impact of the external environment on a person, since it does not correspond to the hereditary and acquired properties of the body.

The impact of climate change on human health is not uniform across the world. The populations of developing countries, especially small island states, arid and high mountain areas, and densely populated coastal areas, are considered to be particularly vulnerable.

Sociality is the specific essence of a person, which, however, does not abolish his biological principle. Social factors in varying degrees affect the physical development of young people and adult members of society, their views and activity in relation to physical education to ensure their optimal life.

The society is interested in strengthening the health of its members and should take effective measures to provide the younger generation and representatives of all age groups with proper conditions for biologically necessary additional physical exercises and various active sports.

Adaptation of the body is the physiological basis of the functional and motor improvement of a person.

Adaptation is the adaptation of the sense organs and the body to new, changed conditions of existence. This is one of the most important features of living systems. There are biological, in particular psychophysiological, adaptation and social adaptation.

Physiological adaptation - a set of physiological reactions that underlie the adaptation of the body to changes in environmental conditions and directed towards maintaining the relative constancy of its internal environment - homeostasis.

Thus, adaptation and homeostasis are interacting and interrelated concepts.

The structure of physiological adaptation is dynamic, it is constantly changing. It may include various organs, various physiological and functional systems.

General and local effects of physical activity on the human body.

The body of each person has certain reserve capabilities in resisting the influences of the external environment.

The overall effect of regular exercise (training) is to:

Positive changes in the musculoskeletal system: the mass and volume of skeletal muscles increase, their blood supply improves, tendons and ligaments of the joints become stronger, etc .;

Economization of the functions of individual organs and blood circulation in general; in improving the composition of the blood, etc.;

Reducing energy consumption at rest: due to the economization of all functions, the total energy consumption of a trained organism is lower than that of an untrained one by 10–15%;

A significant reduction in the recovery period after physical activity of any intensity.

The local effect of increasing fitness, which is an integral part of the general effect, is associated with an increase in the functionality of individual physiological systems.

The human body is 60% water. Adipose tissue contains 20% water (of its mass), bones - 25, liver - 70, skeletal muscles - 75, blood - 80, brain - 85%. For the normal functioning of an organism that lives in a changing environment, the constancy of the internal environment of the organism is very important. It is created by blood plasma, tissue fluid, lymph, the main part of which is water, proteins and mineral salts. Water and mineral salts do not serve as nutrients or energy sources.

The exchange of water and electrolytes, in essence, is a single whole, since biochemical reactions occur in aqueous media, and many colloids are highly hydrated, i.e. connected by physical and chemical bonds with water molecules.

The need for nutrient intake directly depends on how much energy a person consumes in the course of his life.

When exercising, the body adapts to physical activity. It is based on metabolic changes that occur during the muscle activity itself and make up its molecular mechanism. It should be immediately noted that for adaptation processes both directly in the muscular system and in other organs, repeated use of physical activity is necessary.

Energy exchange. Energy costs.

The exchange of substances between the organism and the external environment is accompanied by an exchange of energy. The most important physiological constant of the human body is the minimum amount of energy that a person spends in a state of complete rest. This constant is called the basal exchange. Its value depends on body weight: the larger it is, the greater the exchange, but this dependence is not straightforward. The energy requirement of the body is measured in kilocalories.

The energy balance in the life of a modern person is very often significantly disturbed. In economically developed countries for the last.

Working capacity. Her recovery.

Efficiency is manifested in maintaining a given level of activity for a certain time and is determined by two main groups of factors - external and internal. External - the information structure of signals (the number and form of presentation of information), the characteristics of the working environment (the convenience of the workplace, illumination, temperature, etc.), relationships in the team. Internal - the level of training, fitness, emotional stability. Working capacity limit -- variable value; its change in time is called the dynamics of performance.

Fatigue. Fatigue.

Fatigue is a physiological state of the body that occurs as a result of excessive mental or physical activity and is manifested by a temporary decrease in performance.

Fatigue is a subjective experience, a feeling that usually reflects fatigue, although it can sometimes occur without real fatigue.

Hypokinesia. Physical inactivity.

Hypokinesia is a special condition of the body due to lack of physical activity. In some cases, this condition leads to hypodynamia.

Hypodynamia (decrease; strength) - a set of negative morphological and functional changes in the body due to prolonged hypokinesia. These are atrophic changes in the muscles, general physical detraining, detraining of the cardiovascular system, a decrease in orthostatic stability, changes in the water-salt balance, changes in the blood system, bone demineralization, etc.

Under conditions of hypodynamia, the strength of heart contractions decreases due to a decrease in venous return to the atria, the minute volume, heart mass and its energy potential decrease, the heart muscle weakens, and the amount of circulating blood decreases due to its stagnation in the depot and capillaries.

Influence of biorhythms on physiological processes and working capacity.

The repeatability of processes is one of the signs of life. At the same time, the ability of living organisms to sense time is of great importance. With its help, daily, seasonal, annual, lunar and tidal rhythms of physiological processes are established. Studies have shown that almost all life processes in a living organism are different.

The rhythms of physiological processes in the body, like any other repetitive phenomena, have a wave-like character. The distance between the same positions of two oscillations is called a period, or a cycle.

Biological rhythms or biorhythms are more or less regular changes in the nature and intensity of biological processes. The ability for such changes in vital activity is inherited and found in almost all living organisms. They can be observed in individual cells, tissues and organs, in whole organisms and in populations.

The strongest effect is the rhythmically changing radiation of the Sun. On the surface and in the bowels of our luminary, processes are continuously going on, manifesting themselves in the form of solar flares.

Physical mechanisms of formation and improvement of motional actions.

The central nervous system regulates, controls and improves human motor activity through motor units. The motor unit consists of a motor nerve cell, a nerve fiber, and a group of muscle fibers.

By changing the strength and frequency of bioelectric impulses, processes of excitation and inhibition arise in nerve cells. Excitation is the active state of cells when they transform and transmit electrical impulses to other cells.

The physiological basis for the formation of motor skills is the existing or emerging temporary connections between the nerve centers (sometimes they say that he (she) has a good motor base). In a number of cases in everyday life, in professional work and, especially, in various sports, so-called motor stereotypes are formed at the level of skills.

Sport. The fundamental difference between sports and other types of physical exercises.

Sport is a generalized concept denoting one of the components of the physical culture of society, historically formed in the form of competitive activity and special practice of preparing a person for competitions.

Sport differs from physical culture in that it has an obligatory competitive component. Both an athlete and an athlete can use the same physical exercises in their classes and trainings (for example, running), but at the same time, an athlete always compares his achievements in physical improvement with the successes of other athletes in full-time competitions. The exercises of an athlete are aimed only at personal improvement irrespective of the achievements in this field of other practitioners. That is why we cannot call an athlete a cheerful old man moving along the alleys of the square "jogging" - a mixture of fast walking and slow running. This respected person is not an athlete, he is an athlete using walking and running to maintain their health and performance.

Grassroots sports

Mass sports enable millions of people to improve their physical qualities and motor abilities, improve their health and prolong creative longevity, and thus resist the undesirable effects on the body of modern production and everyday life conditions.

The purpose of practicing various types of mass sports is to improve health, improve physical development, fitness and actively relax. This is due to the solution of a number of particular tasks: to increase the functionality of individual body systems, to correct physical development and physique, to increase general and professional performance, to master vital skills and abilities, to spend leisure time pleasantly and usefully, to achieve physical perfection.

The tasks of mass sports largely repeat the tasks of physical culture, but are realized by the sports orientation of regular classes and training.

A significant part of young people join the elements of mass sports during their school years, and in some sports even at preschool age. It is mass sports that are most widespread in student groups.

Sports of the highest achievements

Along with mass sports there is a sport of the highest achievements, or big sport. The goal of big sport is fundamentally different from the goal of mass sports. This is the achievement of the highest possible sports results or victories in major sports competitions.

Any highest achievement of an athlete is not only of personal importance, but becomes a national treasure, as records and victories in major international competitions contribute to strengthening the country's authority on the world stage. Therefore, it is not surprising that the largest sports forums gather billions of people on TV screens around the world, and among other spiritual values, world records, victories at world championships, and leadership at the Olympic Games are so highly valued.

To achieve the goal in big sport, stage-by-stage plans for long-term training and corresponding tasks are being developed. At each stage of preparation, these tasks determine the necessary level of achievement of the functional capabilities of athletes, their mastery of techniques and tactics in their chosen sport. All this in total should be realized in a specific sports result.

Unified sports classification. National sports in sports classification.

To compare the level of results achieved both in one sports discipline and between different sports, a single sports classification is used.

The current sports classification includes almost all sports cultivated in the country. It is very conditional, in a single gradation of sports titles and categories, there are standards and requirements that characterize the level of preparedness of athletes, their sports results and achievements.

What is body fitness? Let's say you decide to go for a run for the first time after school, university or the army, where sports were a mandatory part of the process. Suppose, on your first exit to the track, you mastered one circle with a breath and curses. The next day, you will run the same circle almost calmly. On the third training session, it will be very easy to overcome the circle: it means that you can increase the distance. Step by step, gradually increasing the load, you teach the body to cope with it. In a month you can freely run a kilometer, in six months - ten. Look at the person you were 6 months ago: for him, running 10 km was as impossible as flying into space. However, with training, the boundaries of possibilities are pushed apart.

It is impossible to cope with the load indefinitely, someday any athlete reaches the peak of his form - to the level of results above which he physically cannot rise.

Over many years of training, the body in ordinary life learns to live in a more economical mode. In stayers, for example, the pulse at rest is 40-55 beats per 1 minute (the normal pulse of an untrained person is 60-80 beats per 1 minute); reduced pressure, approximately 100/60 mm Hg. Art. (norm - 120/80), which excludes the possibility of heart attacks, with an increase, it will not go beyond critical values; the number of breaths per minute decreases to 12-14 versus 16-20 in untrained people, the depth of breathing increases. However, all these positive phenomena can be observed only with the correct construction of training. Otherwise, there is a high probability that the functioning of the organs will deteriorate. The correct training process of a runner consists not only of increasing the mileage, but also of strength training (to strengthen the muscular corset and muscles of the limbs), active games (,) for the development of speed skills - for recovery. For an athlete participating in competitions, the annual training cycle is divided into several stages:

preparatory (general and special physical training);

competitive (set, preservation and temporary reduction of sports form);

transitional (active and passive rest).

This division is due to the fact that an athlete cannot be at the peak of form for a long period of time, therefore the entire training process performs the main task - to bring the athlete to the peak of form during important starts.

Morphofunctional and metabolic characteristics of fitness

To characterize the state of fitness, physiological indicators are examined at rest, during standard (non-maximal) and limit loads. In trained individuals at rest, as well as during the performance of standard non-maximum loads, function economization phenomenon- less pronounced functional changes than in untrained or poorly trained individuals. In the case of using maximum physical activity, it is noted maximum functionality amplification phenomenon to limit values (Bepotserkovsky, 2005; Dubrovsky, 2005; Kots, 1986).

IN resting state the fitness of the body is evidenced by: left ventricular hypertrophy in 34% of cases and in 20% - hypertrophy of both ventricles, an increase in heart volume (up to a maximum of 1700 cm3), a slowdown in heart rate to 50 beats-min -1 and less (bradycardia), sinus arrhythmia and sinus bradycardia, changes in the characteristics of the P and T waves. In the external respiration apparatus, an increase in VC (up to a maximum of 9000 ml) is noted due to the development of the respiratory muscles, a slowdown in the respiratory rate to 6-8 cycles per minute. The breath holding time increases (up to about 146 s), which indicates a greater ability to tolerate hypoxia.

In the blood system of athletes at rest, the volume of circulating blood increases by an average of 20%, the total number of erythrocytes, hemoglobin (up to 170 gg1), which indicates a high oxygen capacity of the blood.

The indicators of the fitness of the motor apparatus are: reduction of motor chronaxy, reduction of the difference in the values of chronaxy of antagonist muscles, increase in the ability of muscles to tension and relax, improvement of proprioceptive sensitivity of muscles, etc.

During standard (non-maximal) physical activity indicators of fitness are the lower severity of functional changes in trained individuals compared to untrained ones.

During extreme physical activity there is a phenomenon of increasing the implementation of functions: heart rate rises to 240 beats min -1, IOC - up to 35-40 l-min -1, pulse pressure increases, LV reaches 150-200 l min, V0 2 max-6--7 l-min -1, MKD-22 l and more, the maximum concentration of lactate in the blood can reach 26 mmol-l-1, blood pH shifts towards lower values (to pH = 6.9), blood glucose concentration can decrease to 2, 5 mmol-l-1, PANO in trained individuals occurs when oxygen consumption is at a level of 80-85% V0 2 max (Dubrovsky, 2005; Kurochenko, 2004; Physiological mechanisms of adaptation, 1980; Physiological testing of athletes ..., 1998).

In load testing, physical loads that meet the following requirements should be used:

so that the work performed can be measured and subsequently reproduced;

to be able to change the intensity of work within the required limits;

so that a large mass of muscles is involved, which provides the necessary intensification of the oxygen transport system and prevents the occurrence of local muscle fatigue;

be fairly simple, affordable and do not require special skills or high coordination of movements.

In stress testing, bicycle ergometers or hand ergometers, steps, treadmills are usually used (Physiological testing of athletes ..., 1998; Sports medicine. Practical ..., 2003).

advantage bicycle ergometry is that the load power can be clearly dosed. The relative immobility of the head and hands during pedaling makes it possible to determine various physiological parameters. Electromechanical vepoergometers are especially convenient. Their advantage is that in the process of work it is not necessary to monitor the pace of pedaling, changing it within certain limits does not affect the power of work. The disadvantage of bicycle ergometry is the occurrence of local fatigue in the muscles of the lower extremities, which limits work during intense or duration of physical exertion.

steppergometry- a simple method of dosing loads, which is based on a modified step climb, which allows you to perform the load in the laboratory. The power of work is regulated by changing the height of the step and the rate of ascent.

One-, two-, three-step ladders are used, which can vary in the height of the steps. The pace of ascent is set by a metronome, a rhythmic sound or light signal. The disadvantage of stepergometry is the low accuracy of dosing the load power.

Threadban allows you to simulate locomotion - walking and running in the laboratory. The load power is dosed by changing the speed and angle of the moving belt. Modern treadmills are equipped with automatic ergometers, heart rate recorders or gas analyzers with computer software, which allow you to accurately control the load power and obtain a large number of absolute and relative functional indicators of gas exchange, blood circulation, and energy metabolism.

The most common are these types of loads (Mishchenko V.S., 1990; Levushkin, 2001; Solodkov, Sologub, 2005).

1. Continuous load of constant power. The power of work can be the same for all subjects or vary depending on gender, age and physical fitness.

2. Stepwise increasing load with an interval of rest after each "step".

3. Continuous operation at a uniformly increasing power (or almost uniformly) with a rapid change of the next steps without rest intervals.

4. Stepwise continuous load without rest intervals.

Assessment of the state of fitness of athletes according to the functional indicators of the motor apparatus and sensory systems

Study of the functional state of the motor apparatus. Under the influence of training sessions, adaptive changes occur not only in the active part of the motor apparatus - muscles, but also in bones, joints and tendons. The bones become coarser and stronger. They form roughness, protrusions, providing better conditions for attaching muscles and preventing injury.

More significant changes occur in the muscles. The mass and volume of skeletal muscles (working hypertrophy), the number of blood capillaries increase, as a result of which more nutrients and oxygen enter the muscles. If untrained individuals have 46 capillaries per 100 muscle fibers, then well-trained athletes have 98 capillaries. Due to increased metabolism, the volume of individual muscle fibers increases, their shell thickens, the volume of sarcoplasm, the number of myofibrils increase, and, as a result, the volume and mass of muscles , which is 44-50% of body weight or more in athletes of various specializations (Alter, 2001; Kozlov, Gladysheva, 1997; Sports medicine. Practical ..., 2003).

The functional properties of the motor apparatus are largely determined by the composition of the muscles. Thus, speed and strength-oriented exercises are performed more efficiently if fast-twitch (TS) fibers predominate in the muscles, and exercises with the manifestation of endurance - with a predominance of slow-twitch (MS) muscle fibers. For example, in sprint athletes, the content of BS fibers is on average 59.8% (41-79%). The composition of the muscles is genetically determined, and under the influence of systematic training sessions, there is no transition from one type of fiber to another. In some cases, there is a transition from one subtype of BS fibers to another.

Under the influence of sports training, the supply of energy sources of g-creatine phosphate, glycogen and intracellular lipids, the activity of enzymatic systems, the capacity of buffer systems, etc. increase.

Morphological and metabolic transformations in muscles that occur under the influence of training sessions are the basis of functional changes. Due to hypertrophy, for example, muscle strength increases in football players: leg extensors from 100 to 200 kg, leg flexors - from 50 to 80 kg or more (Dudin, Lisenchuk, Vorobyov, 2001; Evgenyeva, 200 2).

The muscles of trained people are more excitable and functionally mobile, as judged by the time of a motor reaction or the time of a single movement. If the motor reaction time for untrained individuals is 300 ms, then for athletes it is 210-155 ms or less (Filippov, 2006).

The study of muscle strength of athletes using dynamometers

Equipment: dynamometers (manual and deadlift).

Progress

With the help of a manual (carpal) dynamometer, the strength of the muscles of the hand and forearm of several subjects (preferably of different specializations) is measured. Measurements are carried out three times, take into account the largest indicator. A high indicator is considered to be a value that is 70% of body weight.

The back is measured with a back dynamometer. Each student is tested three times, taking into account the maximum result. The analysis of the obtained indicators is carried out taking into account the body weight of the subjects, using the following data:

The obtained indicators of the strength of the muscles of the hand and forearm, as well as the backbone strength of all subjects are analyzed and conclusions are drawn.

Study of the functional stability of the vestibular apparatus using the Yarotsky test

Muscular activity is possible only when the central nervous system receives information about the state of the external and internal environment of the body. Such information enters the central nervous system through special formations - receptors, which are highly sensitive nerve endings. They can be part of the sense organs (eye, ear, vestibular apparatus) or function independently (skin temperature receptors, pain receptors, etc.). The impulses that occur during stimulation of the receptors reach different parts of the central nervous system through sensory (centripetal) receptors and signal the nature of the influence of the external environment or the state of the internal environment. In the central nervous system, they are analyzed and a program of adequate response is created. Formations, including the central nervous system, the centripetal nerve and the sense organ, are called analyzers.

Each sport is characterized by the participation of leading analyzers. First of all, for non-standard variable sports (all sports games, martial arts, skiing, etc.), muscle and vestibular analyzers are extremely important, which ensure the implementation of techniques (Krutsevich, 1999; Solodkov, Sologub, 2003).

The vestibular apparatus is located in the inner ear. Its receptors perceive the position of the body in space, direction of movement, speed, acceleration. In addition, the vestibular apparatus receives a functional load during abrupt starts, turns, falls and stops. During the performance of physical exercises, it is constantly irritated, and therefore its stability ensures the stability of the performance of technical techniques. With significant irritation of the vestibular apparatus in athletes, the accuracy of actions is disturbed, technical errors appear. At the same time, negative reactions appear that affect the activity of the heart, accelerating or slowing down the heart rate, muscle sensitivity. Therefore, the functional control system should include a methodology for determining the stability of the vestibular apparatus of athletes, primarily the Yarotsky test.

Equipment: stopwatch.

Progress

From among the students, several subjects of different specializations and with different levels of sportsmanship are selected.

The subject, standing with his eyes closed, performs head turns in one direction at a rate of 2 movements in 1 s. Determine the time to maintain equilibrium heat.

Adult untrained persons maintain balance for 27-28 s, well-trained athletes - up to 90 s.

The data obtained during the survey are compared and conclusions are drawn about the vestibular stability of athletes of different specializations and the level of fitness.

Study of some functions of the motor analyzer

Equipment: goniometer or goniometer.

Progress

The subject, under visual control, performs a certain movement 10 times, for example, bending the forearm to 90 °. Then the same movement is performed with closed eyes. During the control of the amplitude of movement in each repetition, the magnitude of the deviation (error) is noted.

Conclusions are drawn about the level of muscular-articular sensation for performing movements of a given amplitude.

Determination of an athlete's fitness by assessing resistance to hypoxia

Breath-holding tests (Stange and Genchi)- these are simple methods for studying the body's resistance to hypoxia, which is one of the characteristic signs of the body's fitness.

Equipment: stopwatch.

Progress

From among the students, subjects of different sports specialization and fitness level are selected.

1. Having inhaled, the subject holds his breath as long as possible (nose pinched with fingers). At this point, start the stopwatch and record the breath holding time. With the beginning of exhalation, the stopwatch is stopped (Stange test). In healthy untrained individuals, the breath holding time ranges from 40-60 s for men and 30-40 s for women. In athletes, this figure increases to 60-120 s for men and 40-95 s for women.

2. Having exhaled, the subject holds his breath, from this moment the stopwatch is turned on and the time of holding the breath is recorded (Genchi test). With the beginning of inspiration, the stopwatch is stopped. In healthy untrained people, the breath holding time lasts within 25-40 seconds for men and 15-30 seconds for women. Athletes have high rates: up to 50-60 s in men and 30-50 s in women.

The obtained indicators of all subjects are entered into table 50 and appropriate conclusions are drawn.

Table 50 - The value of breath-hold tests, s

test subject	Stange test	Genchi test

Assessment of the state of fitness according to the cardiovascular and respiratory systems of the body (Rufier test)

Equipment: stopwatch.

Progress

From among the students, several subjects with different levels of preparedness are selected, who take turns performing the Rufier test.

In the subject, who is in the supine position for 5 minutes, determine the heart rate for 15 s (P1). Then, within 45 seconds, he performs 30 squats, after that he lies down and his heart rate is again calculated for the first 15 seconds (P2), and then for the last 15 from the first minute of recovery (P3). The Rufier index is calculated by the formula:

Rufier index \u003d 4 (P1 + P2 + P3) -200 / 10

The assessment of the functional reserves of the heart is carried out by comparing the data obtained with the following:

The results of the study are analyzed, conclusions are drawn about the level of functional reserves of the heart in the subjects.

Muscle training

Muscle training affects the ability to perform physical exercises. Muscle fitness can be assessed in several different ways. Sports clubs offer a number of simple methods.

Rice. 2. Decrease in the dynamically recorded average spectral frequency of the electrical activity of the paraspinal muscles of the left side at the level of the fifth lumbar vertebra and the first sacral vertebra of trained (A) and less trained (B) men when performing dynamic back and forth movements with weighting on the simulator for stretching the back muscles. The decrease in a less trained person occurs much faster than in a trained person.

The indirect way is to measure the force/torque of the upper and lower extremities, as well as the upper body and neck, using various simulators - isokinetic, isotonic and isometric. The limitation of these methods is that they determine the activity or power developed by one specific muscle or group of muscles.

Simultaneous surface electromyography helps to describe the work of all muscles, and the muscles involved in the creation of force can also be easily identified.

Electrical activity can be recorded without causing pain or disturbance to a person using skin electrodes attached to the skin over the muscle being examined; as in electrocardiography, where they are stuck to the chest and extremities. When muscles are loaded in standard ways, there is a linear increase in electrical activity. A strong person can lift a much heavier load than a weak person, since the muscle fibers of a strong person are larger. In the muscles of a weak person, there is a higher electrical activity than in the muscles of a strong one, if they lift the same load. When the muscles get tired, electrical activity increases over time if the muscles experience the same load for a long time. With an increase in electrical activity, the low frequency components of the electromyographic spectrum also increase, while the high frequency components tend to be blocked, since by their nature they are designed to perform short-term tasks.

This transition to lower frequencies can be easily calculated during tiring physical activity, and simple indicators such as average frequency, for example, during two-minute tests (Fig. 2), provide the necessary information about muscle fitness. If the muscles of the trunk are of interest, holding the body in the same position, for example, the upper body over the edge of the table, can be used as a standard load, and the electrical activity of the paraspinal muscles can be recorded. A more specific load can be achieved on a special training chair. The muscles of the trunk are important in any physical activity, and their fitness plays an important role in maintaining balance and standing. If the trunk muscles are poorly developed, the risk of lower back pain increases, especially if a person happens to lift something heavy using the wrong technique.

By monitoring electrical activity during training programs, you can get objective data on progress in sports as fitness increases and fatigue decreases. This method is especially valuable when observing muscles that are difficult to examine in any other way. The pelvic floor muscles play an important role. A sedentary lifestyle, decreased levels of the hormone estrogen as a result of aging, obesity and repeated childbirth are the most common causes of muscle deterioration. Urinary incontinence is one of the most annoying problems for middle-aged women, but it also occurs in men. Training the pelvic floor muscles is one of the most difficult tasks. A physiological solution is the use of biofeedback with the installation of electromyographic sensors in the vagina. Audiovisual feedback leads the patient to continue pelvic muscle exercises with a positive response to therapy, and improvements in pelvic muscle condition can be recorded after one to three months of exercise.