The impact of recreational physical education on health
By the degree of impact on the body, all types of health-improving physical culture (depending on the structure of movements) can be divided into two large groups: exercises of a cyclic and acyclic nature. Cyclic exercises are such motor acts in which the same complete motor cycle is constantly repeated for a long time. These include walking, running, skiing, cycling, swimming, rowing. In acyclic exercises, the structure of movements does not have a stereotypical cycle and changes during their execution. These include gymnastic and strength exercises, jumping, throwing, sports games, and martial arts. Acyclic exercises affect the functions of the musculoskeletal system, as a result of which muscle strength, reaction speed, flexibility and mobility in the joints, and lability of the neuromuscular system increase. Types with the predominant use of acyclic exercises include hygienic and industrial gymnastics, classes in health and general physical training (GPT) groups, rhythmic and athletic gymnastics, gymnastics according to the "Hatha-Yoga" system.
Morning hygienic gymnastics
Morning hygienic gymnastics helps to bring the body into working condition more quickly after waking up, maintain a high level of performance during the working day, improve the coordination of the neuromuscular system, the activity of the cardiovascular and respiratory systems. During morning gymnastics and subsequent water procedures, the activity of skin and muscle receptors, the vestibular system, increases the excitability of the CNS, which helps to improve the functions of the musculoskeletal system and internal organs.
Rhythmic gymnastics
The peculiarity of rhythmic gymnastics is that the pace of movements and the intensity of the exercises are set by the rhythm of the musical accompaniment. It uses a complex of different means that affect the body. Thus, a series of running and jumping exercises affect mainly the cardiovascular system, inclines and squats - and the musculoskeletal system, relaxation methods and. autosuggestion - and the central nervous system. Exercises on the floor develop muscle strength and mobility in the joints, running series - and endurance, dance - and plasticity, etc. Depending on the choice of means used, rhythmic gymnastics classes can be predominantly athletic, dance, psychoregulatory or mixed in nature. The nature of energy supply, the degree of strengthening of respiratory and circulatory functions depend on the type of exercises.
A series of exercises of a parterre nature (in lying, sitting positions) has the most stable effect on the circulatory system. The heart rate does not exceed 130-140 beats/min, that is, it does not go beyond the aerobic zone; oxygen consumption increases to 1.0-1.5 l/min; the lactic acid content does not exceed the level of the ANSP and about 4.1 mmol/l. Thus, work in the parterre is predominantly aerobic in nature. In a series of exercises performed in a standing position, local exercises for the upper extremities also cause an increase in heart rate to 130-140 beats/min, dance movements - and up to 150-170, and global (bends, deep squats) - and up to 160-180 beats/min. The most effective effect on the body is exerted by a series of running and jumping exercises, in which at a certain pace the heart rate can reach 180-200 beats/min, and oxygen consumption - and 2.3 l/min, which corresponds to 100% of the maximum permissible energy intake. Thus, these series are predominantly anaerobic in nature (or mixed with a predominance of the anaerobic component); the lactate content in the blood by the end of the workout in this case reaches 7.0 mmol/l, and the oxygen debt - and 3.0 l (V.V. Mativ, T.S. Lisitskaya, 1985).
Depending on the selection of series of exercises and the pace of movements, rhythmic gymnastics classes can have a sports or health-improving orientation. Maximum stimulation of blood circulation to the level of heart rate 180-200 beats/min can be used only in sports training by young healthy people. In this case, it is predominantly anaerobic in nature and is accompanied by the oppression of aerobic mechanisms of energy supply and a decrease in the value of the MIC. Significant stimulation of fat metabolism with this nature of energy supply does not occur; in this regard, there is no decrease in body weight and normalization of cholesterol metabolism, as well as the development of general endurance and working capacity.
In health-improving classes, the choice of the pace of movements and series of exercises should be carried out in such a way that the training is mainly aerobic in nature (with an increase in heart rate within 130-150 beats / min). Then, along with the improvement of the functions of the musculoskeletal system (increased muscle strength, joint mobility, flexibility), an increase in the level of general endurance is also possible, but to a much lesser extent than when performing cyclic exercises.
Athletic gymnastics
Athletic gymnastics exercises cause pronounced morphofunctional changes (mainly of the neuromuscular system): hypertrophy of muscle fibers and an increase in the physiological diameter of muscles; growth of muscle mass, strength and power endurance. These changes are mainly associated with a long-term increase in blood flow in working muscle groups as a result of repeated repetition of exercises, which improves the trophism (nutrition) of muscle tissue. It should be emphasized that these changes do not contribute to an increase in the reserve capabilities of the circulatory system and - the aerobic productivity of the body. Moreover, as a result of a significant increase in muscle mass, the relative indicators of the most important functional systems deteriorate - and the vital index (VC per 1 kg of body weight) and maximum oxygen consumption (MPC per 1 kg). In addition, the increase in muscle mass is accompanied by an increase in the fat component, an increase in blood cholesterol and an increase in blood pressure, which creates favorable conditions for the formation of the main risk factors for cardiovascular diseases.
When observing 30-year-old men who were engaged in athletic gymnastics for two years, an increase in blood pressure was noted on average from 121/70 to 130/78 mm Hg. (and in 30% of them - to 140/80 mm Hg.), a decrease in the vital index (as a result of an increase in body weight) from 72 to 67 ml / kg, an increase in resting heart rate from 71 to 74 beats / min (Yu. M. Danko, 1974). When performing a functional stress test, the number of atypical reactions to the load increased from 2 to 16 (out of 30 examined), the pulse recovery time - from 2.9 to 3.7 minutes. According to the data of the electrocardiographic study, myocardial overstrain was detected in 12% of those involved.
In addition to the increase in muscle mass, these negative changes are also facilitated by high nervous tension and breath holding during exertion. At the same time, intrathoracic pressure increases sharply, blood flow to the heart, its size and stroke volume decrease; as a result, the myocardial bed decreases and short-term myocardial ischemia develops. With prolonged overloads, which often occur in athletic gymnastics, these changes can become irreversible (especially in people over 40 years old). That is why building muscle mass should not be an end in itself.
Athletic exercises can be recommended as a means of general physical development for young healthy men - and in combination with exercises that contribute to increasing aerobic capacity and general endurance. For example, when combining weight exercises with sports games, an increase in physical performance according to the PWC170 test from 1106 to 1208 kgm/min was noted, and with running training - and up to 1407 kgm/min, while when practicing "pure" athleticism, such an effect was not observed (A.N. Mamytov, 1981). When combining strength exercises with swimming and running (4 times a week - and athletic gymnastics and 2 times - and endurance training), along with a pronounced increase in strength and strength endurance, an increase in the PWC170 test indicators from 1100 to 1300 kgm/min and IBC from 49.2 to 53.2 ml/kg was noted.
It should also be taken into account that strength exercises are accompanied by large drops in blood pressure associated with breath holding and exertion. During exertion, as a result of a decrease in blood flow to the heart and cardiac output, systolic pressure drops sharply and diastolic pressure increases. Immediately after the end of the exercises - and as a result of active blood filling of the ventricles of the heart, the pressure rises to 180 mm Hg. and more, and diastolic pressure drops sharply.
These negative changes can be largely neutralized by changing the training method (working with weights no more than 50% of the maximum weight and lifting the projectile in the inhalation phase), which automatically eliminates breath holding and straining. This method was proposed by specialists in Bulgaria, where athletic gymnastics is widely used for health purposes.
It is necessary to critically consider the feasibility of its use by middle-aged and elderly people (given the age-related changes in the cardiovascular system and the negative impact on risk factors). Athletic gymnastics, as already noted, can be recommended to healthy young people, provided that the training process is optimized and athletic exercises are combined with endurance training (running, etc.). People of more mature age can use only individual exercises of the athletic complex aimed at strengthening the main muscle groups (muscles of the shoulder girdle, back, abdominal press, etc., as a supplement after endurance training in cyclic exercises.
Gymnastics according to the “Hatha-Yoga” system
Despite the fact that this gymnastics is quite popular in our country, its physiological effect on the body has not yet been studied sufficiently. It is quite likely that the range of its influence is very wide - and due to the variety of means used.
Hatha yoga is a component of Indian yoga, which includes a system of physical exercises aimed at improving the human body and the functions of internal organs. It consists of static poses (asanas), breathing exercises and elements of psychoregulation. The effect of asanas on the body depends on at least two factors: strong stretching of nerve trunks and muscle receptors, increased blood flow in a certain organ (or organs) as a result of a change in body position. When receptors are disturbed, a powerful flow of impulses occurs in the CNS, which stimulates the activity of the corresponding nerve centers and internal organs. In the "shirsa-sana" pose (headstand), blood flow to the brain increases, in the lotus pose - and to the pelvic organs. Performing special breathing exercises (controlled breathing) associated with breath holding, in addition to the neuro-reflex effect on the body, helps to increase the vital capacity of the lungs and increases the body's resistance to hypoxia. "Sava-sana" ("dead pose") with complete muscle relaxation and immersion in a semi-drowsy state is used for faster and more complete recovery of the body after strong muscle tension in static poses. Stimulation of recovery processes and increased efficiency of rest occurs due to a decrease in the flow of impulses from relaxed muscles in the CNS, as well as increased blood flow in the working muscle groups.
In recent years, new data have been obtained that during relaxation (as well as during muscle activity) endorphins are released into the blood, as a result of which mood improves and psycho-emotional tension is relieved - and the most important factor in neutralizing psychological stress.
During dynamic observation of young people practicing the "Hatha-yoga" system, a number of positive changes in the body have been identified. Thus, a decrease in resting heart rate and blood pressure was noted, an increase in vital capacity (on average from 4.3 to 4.8 l), as well as an increase in the content of erythrocytes and hemoglobin in the blood and the time of breath holding. The greatest increase was observed in flexibility indicators - from 4.4 to 11.2 cm. No significant increase in aerobic capacity and physical performance level was observed. The PWC170 test increased from 1220 to 1260 kgm/min, and the BMD - from 3.47 to 3.56 l/min, which is statistically unreliable (Janaraj, 1980). Recent studies have shown a positive effect of yoga on patients with bronchial asthma and hypertension (controlled breathing and psychoregulation techniques), and a decrease in blood circulation and an increase in tolerance to physical exertion are also noted.
Thus, the "hatha yoga" system can be used in health physical culture. For example, such exercises as abdominal and full breathing of yogis, autogenic training (which, in fact, is a variant of the "dead pose"), some flexibility exercises are successfully used. ("plow", etc.), elements of body hygiene and nutrition, etc. However, gymnastics according to the "hatha yoga" system, obviously, cannot act as a sufficiently effective independent health-improving tool, because it does not lead to an increase in aerobic capacity and the level of physical performance. The population of India, despite mass classes in the "hatha yoga" system, has the lowest PMK indicators in comparison with other nations. It is also necessary to take into account that the system of classes that gives positive results in the conditions of India cannot be mechanically transferred to our environment with an unfavorable ecological situation, a busy pace of life, a shortage of free time and the absence of experienced methodologists. The "Hatha Yoga" system requires performing asanas early in the morning in the fresh air (in a park, forest, by the sea), and after the class, complete relaxation is required for at least 15-20 minutes. It is unlikely that all this is done in modern society.
The above-described forms of health-improving physical culture (using acyclic exercises) do not contribute to a significant increase in the functional capabilities of the circulatory system and the level of physical performance, and therefore do not have a decisive importance as health-improving programs. The leading role in this regard belongs to cyclic exercises, which ensure the development of aerobic capabilities and general endurance.
As can be seen, the highest indicators of aerobic power are those of representatives of cyclic sports - skiers, runners, cyclists. In athletes of acyclic sports (gymnastics, weightlifting, throwing) the value of MIC does not exceed the indicators of untrained men - 45 and 42 ml/kg. Increasing aerobic capacity and general endurance (I THINK is the most important property of all cyclic exercises. Therefore, they were called aerobic, or simply aerobics (according to Cooper).
Aerobics
This is a system of physical exercises, the energy supply of which is carried out by using oxygen. Aerobic only includes those cyclic exercises in which at least 2/3 of the body's muscle mass participates. To achieve a positive effect, the duration of aerobic exercises should be at least 20-30 minutes, and the intensity should not be higher than the level of the ANSP. It is for cyclic exercises aimed at developing general endurance that the most important morphofunctional changes in the circulatory and respiratory systems are characteristic: an increase in the contractile and "pumping" function of the heart, improved utilization of oxygen by the myocardium, etc. The differences between individual types of cyclic exercises, associated with the peculiarities of the structure of the motor act and the technique of its execution, are not of fundamental importance for achieving preventive and health-improving effect.
Health-improving walking
Health-improving (accelerated) walking is widely used in mass physical culture: at an appropriate speed (up to 6.5 km/h), its intensity can reach the training mode zone (heart rate 120-130 beats/min). In the USA, for example, 53 million Americans are engaged in accelerated walking (according to the Gallup Institute). Under such conditions, 300-400 kcal of energy is spent per hour of walking, depending on body weight (approximately 0.7 kcal/kg per 1 km of distance traveled). For example, a person weighing 70 kg spends about 50 kcal (70XO.7) when walking 1 km. At a walking speed of 6 km/h, the total energy expenditure will be 300 kcal (50*6). With daily health-improving walking (1 hour each), the total energy expenditure per week will be about 2000 kcal, which provides a minimum (limit) training effect - and to compensate for the deficit of energy expenditure and the growth of the body's functional capabilities.
This is confirmed by the results of a study of maximum aerobic performance. Thus, after 12 weeks of training in health walking (1 hour 5 times a week), the subjects observed an increase in BMD by 14% compared to the initial level. However, such a training effect is possible only in unprepared beginners with low UFI. In more prepared athletes, the health effect of walking decreases, because with increasing fitness, the intensity of the load becomes below the limit. Increasing the walking speed by more than 6.5 km/h is difficult, because it is accompanied by a disproportionate increase in energy expenditure. That is why when moving at a speed of 7 km/h and slower, it is easier to run than to walk fast.
Accelerated walking as an independent health remedy can be recommended only if there are contraindications to running (for example, in the early stages of rehabilitation after a heart attack). In the absence of serious deviations in health, it can be used only as the first (preparatory) stage of endurance training in beginners with low functional capabilities. In the future, as fitness increases, health walking should be replaced by running training.
A group of scientists from the University of Washington observed 11 men and women aged 60-65 years, who were overweight (an average of 75.3 kg with a height of 161 cm) and had impaired cholesterol metabolism. At the first stage of training, low-intensity loads were used for 6 months: health walking at a heart rate of 60% of the maximum (5 times a week for 30 minutes); after that, an increase in BMD by 12% compared to the initial level was noted. The next 6 months, the intensity of classes was increased to 80% of the maximum heart rate (running); as a result, BMD increased by another 18%, blood cholesterol decreased, and HDL content increased by 14%.
Interesting data on the combined effect of long walking on the body in combination with a low-calorie diet are provided by Finnish scientists. 13 women and 10 men during a 7-day walking trip covered 340 km, walking an average of 50 km per day (at a speed of 3.5 km/h). Their diet consisted of water, including mineral water, fruit juices and several natural products. During this time, body weight decreased by 7%, cholesterol and triglycerides in the blood - by 30-40%, and HDL increased by 15%. In the evening, a sharp decrease in blood glucose and insulin was observed. Despite this, the working capacity of the subjects remained at a fairly high level. The authors note that metabolic shifts in the body were significantly greater than with the separate use of walking and fasting.
In the conditions of the modern world with the advent of devices that facilitate labor activity (computer, technical equipment), people's physical activity has sharply decreased compared to previous decades. This ultimately leads to a decrease in the functional capabilities of a person, as well as to various kinds of diseases.
Intellectual work sharply reduces the body's working capacity. But physical work, characterized by increased physical exertion, can in some cases be viewed from the negative side.
In general, the lack of energy expenditure necessary for a person leads to inconsistency of the activity of individual systems (muscular, skeletal, respiratory, cardiovascular) and the body as a whole with the environment, as well as to a decrease in immunity and a deterioration in metabolism.
At the same time, overloads are also harmful. Therefore, both during mental and physical work, it is necessary to engage in health-improving physical culture, to strengthen the body.
Physical culture has a health-improving and preventive effect, which is extremely important, because today the number of people with various diseases is constantly growing.
Physical culture should enter a person's life from an early age and not leave it until old age. At the same time, the moment of choosing the degree of loads on the body is very important, an individual approach is needed here. After all, excessive loads on the human body, both healthy and with any disease, can harm it.
However, as we can see from the results of research, physical education classes at school do not give the desired result. The indicators of strength, speed and flexibility of those who are engaged in extracurricular work in physical education or sports are much higher than those who are not engaged. The same is true of students' health. Health indicators are much better in athletes than in those who are engaged in physical education only at school.