Physical education and hardening Physical education and sports classes Performed by: life safety teacher Agafonov V.G. Speed development, exercises to increase running speed Exercises to develop speed
>>OBZD: Physical education and sports classes
Section III
Regular physical education and sports are a must healthy lifestyle.
The body of a schoolchild is a complex developing system, and for its proper growth, outdoor games, physical education and sports, and hardening procedures are necessary.
Lesson content lesson notes supporting frame lesson presentation acceleration methods interactive technologies Practice tasks and exercises self-test workshops, trainings, cases, quests homework discussion questions rhetorical questions from students Illustrations audio, video clips and multimedia photographs, pictures, graphics, tables, diagrams, humor, anecdotes, jokes, comics, parables, sayings, crosswords, quotes Add-ons abstracts articles tricks for the curious cribs textbooks basic and additional dictionary of terms other Improving textbooks and lessonscorrecting errors in the textbook updating a fragment in a textbook, elements of innovation in the lesson, replacing outdated knowledge with new ones Only for teachers perfect lessons calendar plan for the year; methodological recommendations; discussion program Integrated LessonsThere is no need to convince anyone of the benefits of sports. Everyone loves sports, only some people watch TV, while others go to the gym. Without physical education and sports there will be no harmonious development, no health, no graceful posture.
During changes, you don't need to stay in a sitting position, you need to move. If we are preparing homework at home, we need to take a break every 45 minutes for active muscle activity. This change in mental and physical activity brings rest and maintains ability to work. Our age is the age of physical inactivity, i.e. limited motor activity. Therefore, you need to start your morning with exercise. It will take 5 - 10 minutes and will be a boost of energy for the whole day. On weekends it is better to take a walk in the forest or in the park. You need to strengthen your body in order to always be energetic and cheerful.
Physical education and sports activities
Regular physical education and sports are a prerequisite for a healthy lifestyle.
The body of a schoolchild is a complex developing system, and for its proper growth, outdoor games, physical education and sports, and hardening procedures are necessary.
How do physical exercises and sports affect the development of a growing body?
Under the influence of muscle activity, the development of all parts of the central nervous system and its main link, the brain, occurs. This is very important, because the brain processes a huge flow of information and regulates the coordinated activity of the body.
Physical exercise has a beneficial effect on the development and development of all functions of the central nervous system: strength, mobility and balance of nervous processes. Even mental activity is impossible without movement. That is why schoolchildren who are constantly involved in physical education and sports better learn the material they study.
Systematic training makes muscles stronger and the whole body more adapted to environmental conditions. Under the influence of muscle loads, the heart rate increases, the heart muscle contracts more strongly, and blood pressure becomes optimal. This leads to functional improvement of the circulatory system.
During muscle work, the ventilation capacity of the lungs improves. Intensive full expansion of the lungs eliminates congestion in them and serves as a prevention of possible diseases.
Constant physical exercise helps to increase the mass of skeletal muscles, strengthen joints, ligaments, and bone growth and development. In a strong, seasoned person, mental and physical performance and resistance to various diseases increase.
The data given in Table 20 will help you assess the physical capabilities of your health. In addition, you can assess the level of your physical fitness based on the results obtained in physical education lessons.
To ensure a good level of health, you need to have a strong, trained body with great endurance and good speed.
The development of SPEED QUALITIES gives a person the opportunity to move and jump at maximum speed, which is especially important in various martial arts and sports games.
The main means of developing speed are exercises that require energetic motor reactions, high speed and frequency of movements.
STRENGTH QUALITIES. Strength is understood as a person’s ability to overcome external resistance or counteract it through muscular effort.
Among the strength qualities of a person, the following varieties are distinguished:
Static strength (the ability to hold weights with maximum muscle tension for a given time);
- press force (manifests itself when moving objects with a large mass with maximum effort);
- high-speed dynamic force (it characterizes a person’s ability to move objects with a large mass in a limited time);
- “explosive” strength (the ability to overcome resistance with maximum muscle tension in the shortest possible time);
- shock-absorbing force (it manifests itself when landing in various types of jumps).
Various strength exercises are used to develop muscle strength, primarily exercises with external resistance and overcoming the mass (weight) of one’s own body.
Exercises with external resistance can be different: with weights, with a partner, with the resistance of elastic objects (rubber shock absorbers, various expanders, etc.), with overcoming the resistance of the external environment (running uphill, running on sand, snow, water).
Exercises to overcome the mass (weight) of one’s own body can also be different: gymnastics (pull-ups on the horizontal bar, push-ups while lying down and on uneven bars, rope climbing, etc.), athletics jumping, overcoming obstacles on special training courses.
ENDURANCE is the most important physical quality of a person, which he needs in everyday life, professional activities and when playing sports. It is defined as the ability to maintain a given load necessary to ensure life and resist fatigue that occurs in the process of performing work.
Indicators of a person’s physical performance naturally change with age. During the period of physiological maturation of the body, they grow and reach their maximum values at the age of 18 to 25 years. Then these indicators gradually decrease. In order to maintain their sufficient level longer, you need to develop physical endurance. The most useful for its development are walking, running, skiing, swimming and some other types of physical activity of varying duration and intensity.
Development of FLEXIBILITY - development of the properties of the human musculoskeletal system to expand the limits of movement of individual parts of the body. Develop flexibility with exercises to stretch muscles and ligaments.
Exercises aimed at developing flexibility are based on performing a variety of movements: flexion-extension, bending and turning, rotations and swings. Such exercises can be performed alone or with a partner, with various weights or with simple training devices. Complexes of such exercises can be aimed at developing mobility in all joints to improve overall flexibility without taking into account the specifics of the motor activity of a particular person.
Teenagers usually have very good flexibility and endurance, and they gain strength with age. It is important to always maintain and improve all these qualities in order to preserve them in adulthood.
In table 21 lists the types of physical activities and their role in the development of various physical qualities. They will bring you tangible benefits if you practice at least three times a week. Using the data from this table and table 20, you can, in consultation with your physical education teacher, select exercises that will contribute to the development of your physical qualities.
Hardening the body
Hardening is one of the effective means of strengthening the mechanisms of adaptation of the human body to cold and heat, increasing its resistance to changes in natural conditions.
Hardening weakens or eliminates the body's negative reactions to weather changes (decreased performance, mood swings, malaise, pain in the heart, joints, etc.).
Regular hardening provides:
Increased ability to perceive and remember;
- strengthening willpower;
- active physiological activity and healthy life;
- slowing down the aging process;
- prolongation of active life by 20-25%.
A hardened person is less susceptible to the negative effects of both low and high temperatures.
You can begin to harden your body at any age, but it is better to do this from childhood.
In order to correctly use environmental factors for healing, it is necessary to adhere to the basic principles of hardening. Here they are:
The principle of gradually increasing doses of hardening effects;
- the principle of regularity, obliging the systematic repetition of hardening effects throughout life;
- the principle of taking into account the individual characteristics of the body: the degree of its health, susceptibility to the effects of hardening measures and their tolerance;
- the principle of multifactoriality - the use of several physical agents during hardening: heat, cold, irradiation with visible, ultraviolet, infrared rays, mechanical action of air, water, etc.
There are no absolute contraindications to hardening, but the dose of hardening load at its different stages is important. In the initial hardening mode, low-cooling or low-heating procedures are used in the form of air baths, rubdowns, etc. These procedures are contraindicated only in exceptional cases (in the presence of injury or any disease). People who are practically healthy or have minor deviations in their health can be tempered in this way throughout their lives.
Hardening can be general and local. In general, the irritant affects the entire surface of the body (during air baths, bathing). With local hardening, a limited area of the body (legs, neck, etc.) is exposed.
Low temperatures often have adverse effects on humans. Cooling, depending on the intensity, can cause a variety of undesirable consequences in the body, especially in a weakened person. As a result of cooling, the ability to resist pathogens decreases, the level of metabolic processes decreases, and the activity of the central nervous system is weakened. In unhardened people, all this leads to a weakening of the body and the emergence or exacerbation of a chronic disease.
The combination of exposure to cold and moisture poses a major threat to the health of many people. This situation is possible with damp shoes and clothes.
The role of hardening is especially important in the prevention of colds and acute respiratory diseases. It is known that respiratory diseases in children, adolescents, young men and women are the main cause of disability, various complications, chronic diseases and stressful conditions. Therefore, hardening procedures should be aimed at strengthening the entire body.
When hardening, natural factors are most often used: air, water and sunlight.
Rules for using environmental factors to harden the body
AIR HARDENING. Air baths are healing procedures that should be used throughout your life. If you take air baths indoors, you must first ventilate it. They can also be taken on the balcony, open veranda, in the yard, in the park. Air baths on the shore of a lake, river, or in the forest have the most beneficial effect on the body. The first air procedures should be carried out in a place protected from the wind.
Depending on the thermal sensations, air baths are thermal (above 22 °C), indifferent (21-22 °C), cool (17-20 °C), moderately cold (9-16 °C), cold (0-8 °C). C) and very cold (below 0 °C).
In the initial hardening mode, air baths must be taken in a room with an air temperature of at least 17 °C. You can start taking them at any time of the year in light sportswear. Their duration should be no more than 5 minutes. In the future, it can be increased daily by 5 minutes, and subsequently it can last for hours. Air baths help increase the body's resistance to prolonged exposure to cold.
Twenty-minute air baths are useful to take before bed.
With the help of training, the body must be taught to withstand rapid temperature changes. It is better to start such training in the summer. In the morning, go out into the air and cool down until “goose bumps” appear. From this point on, the procedure should be continued using self-massage, rubbing the skin, and gymnastics for 10-15 minutes. The final stage should be wiping the body with a damp towel. Every day the time from the start of air cooling to the appearance of goose bumps will increase. When this period reaches 3-5 minutes at an air temperature of 12 ° C, you can proceed to the optimal hardening mode.
When hardening in optimal mode, use moderately cold air baths. The guideline for starting massage and gymnastic exercises in this case will also be the appearance of “goose bumps”. After air cooling, it is necessary to carry out water procedures.
Sleeping in the fresh air or with the window open is very beneficial at all times of the year. But you need to start in the summer. at an air temperature not lower than 16-18 ° C. As the air temperature decreases, the thermal insulation properties of the blanket need to be increased (use a second blanket, etc.). Sleeping in the open air strengthens the face and respiratory organs.
SUNBATHING. The effectiveness of solar exposure is determined by the fluxes of ultraviolet, infrared and visible rays.
Sunbathing, including ultraviolet rays, is possible in central Russia from the second half of April. The best time to take them is before noon (especially in summer). Depending on the body's sensitivity to ultraviolet rays, sunbathing can be done under an awning in order to protect from exposure to direct rays.
For health purposes, the sun's rays of the visible and infrared spectrum can be taken in combination with air baths and in the cold season on a glassed-in veranda or in a special solarium.
For those living in the middle zone, the time of the first sunbath should not exceed 20 minutes. It is necessary to ensure uniform exposure to sunlight on all parts of the body. In the future, the time of solar irradiation, with good tolerance, can be gradually increased by 5-10 minutes, bringing it to a maximum duration of 1.5-2 hours.
Sunbathing, taken while moving, has an optimal healing effect, but it must be dosed skillfully, trying to avoid overheating the body. Their use can be combined well with water procedures.
Sunbathing should be taken an hour before meals and no earlier than 1.5 hours after meals. An indicator of the effectiveness and usefulness of sunbathing is your well-being.
To adapt the body for the first 2-3 days, it is advisable to sunbathe in the shade in the nude.
Contraindications for sunbathing are various acute inflammatory diseases, increased excitability of the nervous system and other diseases that require medical supervision.
HARDENING WITH WATER. Water is an excellent hardening agent, as it combines cooling, heating and mechanical properties.
Let's look at the most common and accessible water hardening methods.
3hardening of the nasopharynx as one of the most vulnerable places in the body. It is done by gargling with cool and then cold water.
Pouring feet. This procedure consists of pouring over the lower third of the leg and foot for 25-30 seconds. The initial water temperature is 28-27 °C. Every 10 days it is reduced by 1-2 °C to a final temperature of at least 10 °C. After dousing, the feet are wiped dry. It is better to carry out the procedure in the evening, an hour before bedtime.
Foot baths. The legs are immersed in a bucket or basin of water at an initial temperature of 30-28 ° C. Every 10 days it is reduced by 1-2 °C to a final water temperature of 15-13 °C. The duration of the first baths is 1 minute. Gradually their duration is increased to 5 minutes. It is recommended to move your feet slightly in the water. After the bath they are wiped dry. Foot baths are carried out shortly before bedtime.
Contrasting foot baths. Water with a temperature of 38-40 °C is poured into one container, and water with a temperature of 30-32 °C is poured into the other. First, the legs are immersed in the first container for 1.5-2 minutes, and then in the second for 5-10 seconds. This shift must be repeated 4-5 times. Every 10 days, the temperature in the second container must be lowered by 1-2 °C to a final 15-20 °C, leaving the temperature of the water in the first container unchanged. The duration of immersion in colder water increases to 20 seconds, and the number of changes reaches 8-10 times per procedure.
Walking barefoot - one of the oldest hardening techniques. It can be used from late spring to autumn. Its duration depends on the temperature of the earth. It is especially useful to walk barefoot through dew, after rain, or through water.
Rubbing. It is advisable to carry it out with a terry mitten or a terry towel soaked in water, in the following sequence: arms, legs, chest, stomach, back. Each part of the body is wiped separately, starting from the periphery, and then dried until dry. The duration of the procedure is 1-2 minutes. The water temperature should be reduced by 1 - 2 °C every 10 days. The initial temperature for primary schoolchildren is 32-30 °C in winter and 28-26 °C in summer, the final temperature is 22-20 °C and 18-16 °C, respectively. For middle and older schoolchildren, the initial temperature in winter should be 30-28 °C, and in summer - 26-24 °C, and the final temperature - 20-18 °C and 16-14 °C, respectively. It is advisable to perform wiping in the morning, after exercise.
Pouring water - the most powerful hardening procedure. It is advisable to carry it out in the summer. Pouring is done from a watering can or jug. To avoid the strong mechanical impact of the water flow, you must follow the following sequence of dousing: back, chest, stomach, upper limbs, lower limbs. The initial water temperature for primary schoolchildren in winter should be no lower than 30 °C, and in summer - 28 °C, the final temperature - 20 °C and 18 °C, respectively. Reduce temperature every 10 days. For middle and high school students, the initial water temperature in winter is 28-26 °C, in summer - 24 °C, final - 18-20 °C and 16-15 °C, respectively. The total duration of the procedure is 60-90 seconds. After dousing, the body is wiped dry.
Shower. In this procedure, the mechanical factor is more pronounced. You can use the shower at any time of the year at a temperature of at least 18-20 °C. After physical activity of any nature, it is good to take a contrast shower: alternately warm and cold with a gradually increasing temperature difference (from 5-7 °C to 15-20 °C). The final procedure is a cold shower. The determining criterion is the individual tolerance of the procedure. A contrast shower increases resistance to temperature changes and accelerates recovery processes after physical, intellectual and psycho-emotional stress.
Swimming in open water - a very effective means of hardening, since three factors simultaneously act on the body: sun, air, water. Swimming in open reservoirs can begin when the water temperature in them is stable at a level of at least 20 ° C, and the air temperature is 24-25 ° C. Bathing begins by staying in the water for 4-5 minutes, gradually increasing this time to 15-20 minutes or more. The time spent in water depends on the degree of hardening, meteorological conditions, and age. The best time for swimming is 1.5-2 hours after breakfast and in the afternoon, 2-3 hours after lunch.
Using elevated bath temperatures - a powerful means of healing and hardening. The bath procedure affects the entire body and its functions. Its effect depends on the temperature and humidity in the bath and on the length of stay in it. The use of a bathhouse requires strict control. Its hardening effect consists of repeated exposure of the body to contrasting temperatures.
An indicator of the positive effect of water hardening procedures is the skin reaction. If at the beginning of cooling it turns pale and then turns red, this indicates a positive effect. If skin reactions are mild, this means insufficient exposure. It is necessary to lower the water temperature or increase the duration of the procedure. Sharp paleness of the skin, cyanosis, chills, trembling indicate hypothermia. In this case, you need to increase the temperature or reduce the duration of the procedure, or do both together.
The main idea is that the power developed during the jump exceeds the power of the robot's motors. The idea of storing and releasing energy (power modulation) was borrowed from the animal world, namely from the Senegalese galago, a small African animal with large eyes.
Following the example of the Senegalese galago, the SALTO robot makes a series of sequential jumps, including pushing off vertical walls, as in parkour. Perhaps such machines will find application in the army and the Ministry of Emergency Situations.
When designing the SALTO robot, scientists studied animals with maximum vertical jumping ability. In nature, there are only a few mammals capable of jumping to a height of more than two meters from a resting state, with the ability to immediately repeat such a jump. The record holder among these animals is the Senegalese galago (Galago senegalensis).
A small bot can quite easily make several vertical jumps in a certain sequence: first, it bounces off walls or other surfaces and thus gains height for the jump. In this way, "SALTO" can jump quite high - just over one meter in height.
The robot can also jump quite high “without the help” of a wall. For example, from one place he can jump 90 centimeters. (The developer in the video specifically demonstrates the height of the jump using a ruler.) This is a fairly serious height, considering the dimensions of the bot - its weight is no more than 100 grams, and when extended, its height is just over 25 centimeters.
However, the real jumping ability of "SALTO" surprises you at the moment when it pushes off from the wall to make an even more ambitious jump. Using a vertical surface, the robot can jump at a speed of 1.75 meters per second. Engineers hope the bot's ability could one day be useful in search-and-rescue missions that require quickly moving sensors and bouncing off rocks, for example.
According to scientists, they were inspired to create a jumping robot after talking with specialists from local search and rescue teams. They have entire areas at their disposal that simulate, for example, destroyed buildings. There are giant piles of rubble there that can give an idea of the destruction.
"We wanted to create a search-and-rescue robot that was small enough that its weight wouldn't destroy those boulders, but could move quickly through destroyed buildings," says roboticist Duncan Haldane.
And, as often happens, researchers began to take a closer look at animals in order to equip their robot with unprecedented jumping ability. The choice fell on monkeys.
There is always a biometric component in robotics - this is one of the possible approaches to creating devices, thanks to which robots are modeled after animals. Let's say that engineers recently created a robot puppy that can run up stairs and jump over fences.
In the case of SALTO, the robot is designed in such a way that it can imitate the movement of galagos, a small African primate that is considered one of the most agile animals.
Galagos navigate their way to a nearby tree by jumping, jumping from one vertical surface to another. Using this method of movement, monkeys can reach heights of up to nine meters in just five seconds.
In the future, the researchers want to implement cameras and a recognition system in the robot so that SALTO can map the environment and choose a path among various obstacles.
1.Agreement about speed qualities
Speed qualities are characterized by a person’s ability to perform motor actions in a minimum period of time for given conditions. It is assumed that the task lasts a short time and fatigue does not occur.
It is customary to distinguish three main (elementary) types of manifestation of speed qualities:
1) speed of single movement (at low external resistance);
2) frequency of movements;
3) latent reaction time.
There is very little correlation between single movement speed, movement frequency, and reaction latency across individuals. For example, you can have a very fast reaction and be relatively slow in your movements and vice versa. With this in mind, they say that the elementary varieties of speed qualities are relatively independent of each other.
In practice, one usually encounters complex manifestations of speed qualities. Thus, in sprint running, the result depends on the reaction time at the start, the speed of individual movements (push-off, bringing the hips together in the unsupported phase) and the frequency of steps. The speed achieved in a holistic, complexly coordinated movement depends not only on the speed qualities of the athlete, but also on other reasons (for example, running speed depends on the length of steps, and that, in turn, on the length of the legs, strength and repulsion technique), therefore, it only indirectly characterizes speed qualities, and upon detailed analysis, it is the elementary forms of manifestation of speed qualities that turn out to be the most indicative.
In movements of a cyclic nature, the speed of movement is directly determined by the frequency of movements and the distance covered in one cycle (the length of the “step”):
f=frequency l- step length
With an increase in sports qualifications (and, consequently, with an increase in the maximum speed of movement), both components that determine the speed of movement, as a rule, increase. However, it is different in different sports. For example, in skating, the main importance is to increase the length of the “stride”, and in swimming, both components are approximately equally important. Given the same maximum walking speed, different athletes may have significant differences in stride length and frequency.
2. Speed dynamics
Speed dynamics is the change in speed of a moving body, that is, a function of the form: v= f(t) or v= f(l), where v is speed, t - time, l - path, f- sign of functional dependence.
In sports, there are two types of tasks that require maximum speed. In the first case, it is necessary to show the maximum instantaneous speed (in jumping - at the moment of take-off; in throwing - when releasing a projectile, etc.); In this case, the speed dynamics are chosen by the athlete himself (for example, he can start moving a little faster or slower). In the second case, it is necessary to perform the entire movement at maximum speed (in the minimum time) (example: sprinting). Here, too, the result depends on the speed dynamics. For example, in sprint running, the best result is achieved in those attempts where the instantaneous speeds in certain segments of the starting acceleration are maximum for a given person.
In many movements performed at maximum speeds, two phases are distinguished: 1) increasing speed (starting acceleration), 2) relative stabilization of speed (Fig. 49). The characteristic of the first phase is the starting acceleration, the second - the distance speed. Thus, the speed curve in sprinting can be described by the equation
v(t)=v m (1-e -kt)
Where v(t) - speed value at time t , v - maximum speed value; e- base of natural logarithms; k-individual parameter characterizing acceleration during acceleration from the start. The larger the value To, the faster the athlete reaches his maximum speed. Values v m And To do not correlate with each other. In other words, the ability to quickly gain “your” maximum speed and the ability to move at high speed are relatively independent of each other. Indeed, the strongest sprinters reach their maximum running speed in approximately the same time as beginners - 5-6 seconds from the moment they leave the start. You can have good starting acceleration and low distance speed and vice versa. In some sports, the main thing is starting acceleration (basketball, tennis, hockey), in others only distance speed is important (long jump), in others, both are important (sprinting).
3. Rate of change of force (force gradient)
The word “speed” is used to denote not only the speed of change in the position of a body or its parts in space, but also the speed of change in other indicators (for example, we can talk about the speed of change in temperature). The force of action that a person exhibits in one attempt is constantly changing. This necessitates studying the rate of change of force - the force gradient. The force gradient is especially important when studying movements where it is necessary to exert great force in the shortest possible time - "explosively". Mathematically, the force gradient is equal to the first derivative of the force
by time:
The force growth curve for a single “explosive” force followed by immediate relaxation has the form shown in Fig. 50. To numerically characterize the force gradient, one of the following indicators is usually used:
1) time to achieve a force equal to half the maximum.
Often this indicator is called the force gradient (this usage is convenient due to its brevity, but is not entirely accurate);
2) quotient of division F mix/ t max. This indicator is called the speed-strength index. It is equal to the tangent of the angle in Fig. 50.
In cases where we are talking about moving your own body
athlete (and not the projectile), it is convenient to use the so-called reactivity coefficient (according to Yu. V. Verkhoshansky):
Fmax/ t max * weight athlete's body
The rate of force development plays a big role in fast movements. Its practical significance is easy to understand from Fig. 51, which shows the curves for the manifestation of force by two athletes - A and B. Athlete A has a large maximum force and a low force gradient; In athlete B, on the contrary, the force gradient is high, and the maximum strength capabilities are small. For long duration of movement ( t> t3 ) when both athletes manage to demonstrate their maximum strength, the advantage goes to the stronger athlete A. If the time to perform the movement is very short (less than t 1, in Fig. 51), then the advantage will be on the side of athlete B.
With increasing athletic skill, the time required to perform movements usually decreases and therefore the role of the force gradient becomes more significant.
Time required to achieve maximum strength ( t max ), is approximately 300-400 ms. The time for manifestation of the force of action in many movements is much shorter. For example, the take-off in running for the strongest sprinters lasts less than 100 ms, the take-off in long jump - less than 150-180 ms, the take-off in high jump - less than 250 ms, the final effort in javelin throwing - approximately 150 ms, etc. In In all these cases, athletes do not have time to demonstrate their maximum strength and the achieved speed depends to a large extent on the force gradient. For example, there is a very large correlation between the height of a standing jump and the reactivity coefficient (the athlete who, with the same body weight, can develop greater repulsion force in the shortest time) jumps higher.
4. Parametric and non-parametric relationships between strength and speed qualities
If an athlete performs the same movement several times (for example, putting a shot put from a place), trying to show the best result in each attempt, and the parameters of the motor task (in particular, the weight of the shot) change, then the magnitude of the action force applied to the shot , and the speed of the nucleus ejection will be related to each other by a parametric dependence.
Under the influence of training, the parametric force-velocity relationship can change in different ways. This is determined by what training tools and methods were used by the athlete (Fig. 52).
It is important that an increase in speed during movements with average resistance (and such resistance in real sports conditions can be, for example, the weight and mass of one’s own body or a projectile) can occur with a different ratio of the increase in strength and speed qualities: in some cases (Fig. 52, A) - due to an increase in speed qualities (v mm) b others (Fig. 52, B) - due to an increase in strength qualities ( Fmm ).
Which way of increasing speed indicators is more beneficial in training depends on many reasons (the athlete’s age, experience, type of sport, etc.), and in particular on the amount of resistance (in % of Fmm ), which an athlete has to overcome: the greater it is, the more important it is to increase strength qualities. This is confirmed, in particular, by the values of nonparametric dependencies between indicators of an athlete’s strength qualities ( Fmm) and speed of movements ( vT) at different resistance values. Thus, in one of the experiments (Yu. I. Smirnov), the correlation coefficients were equal: without weights - 0.131, with weights of 1 kg - 0.327, with weights of 3 kg - 0.630, with weights of 8 kg - 0.824.
Therefore, the greater the amount of resistance overcome, the more profitable it is to increase speed in training. (rt) due to an increase in strength indicators
5. Biomechanical aspects of motor reactions
There are simple and complex motor reactions. A simple reaction is a response with a previously known movement to a previously known (suddenly appearing) signal. An example would be high-speed pistol shooting at silhouettes, running starts, etc. All other types of reactions - when there is no
it is known what exactly needs to be done in response to a signal and what this signal will be like are called complex. In motor reactions there are:
a) sensory phase - from the moment the signal appears until the first signs of muscle activity (usually they are recorded by EMG, i.e., by the appearance of electrical activity in the corresponding muscle groups);
b) premotor phase (electromechanical interval - EMI) - from the appearance of electrical muscle activity to the onset of movement. This component is the most stable and ranges from 25-60 ms;
c) motor phase - from the beginning of the movement to its completion (for example, before hitting the ball).
The sensory and premotor components form the latent response time.
As athletic skill increases, the duration of both the sensory and motor components in complex reactions decreases. However, first of all, the sensory phase is shortened (the athlete needs less time to make a decision), which allows him to perform the movement itself more accurately, calmly and confidently. At the same time, no matter how it contracts, you need to be able to observe the object of the reaction (ball, opponent, etc.) for a sufficient time. When a moving object enters the field of view, the eyes begin to move, as if accompanying it. This eye movement occurs automatically and cannot be voluntarily inhibited or accelerated (however, such studies have not yet been conducted on high-class athletes:
maybe they know how to do it). Approximately 120 ms after the start of the tracking eye movement, an anticipatory turn of the head occurs approximately to the place in space where the object is moving and where it can be “intercepted.” Turning the head also occurs automatically (even in people who are not good at catching a ball), but can be inhibited if desired. If the head turn does not have time to occur and in general if the time of observation of a moving object is short, the success of the reaction decreases (Fig. 53).
In complex reactions, the ability to predict the opponent’s actions (for example, the direction and nature of a blow or throw of a ball or puck) becomes of great importance; Such a skill is called anticipation, and the corresponding reactions are called anticipatory.
As for the motor phase of the reaction, its duration varies for different variants of technical actions. For example, it takes more time to catch a ball than to hit it. Handball goalkeepers have different speeds of movement when defending different corners of the goal; therefore, the distances from which they can successfully repel shots are also different. into different sectors of the goal (Table 6, Vo A. Goluhu, revised) The distances from which the ball can no longer be caught or reflected without anticipation are sometimes called the “dead zone”.
Similar patterns exist in other sports games.
Regular physical education and sports are a prerequisite for a healthy lifestyle. A schoolchild’s body is a complex developing system, and for its proper growth, outdoor games, physical education and sports, as well as hardening procedures are necessary. How do physical exercises and sports affect the development of a growing body?
Under the influence of muscle activity, the development of all parts of the central nervous system and its component, the brain, occurs. This is very important because... The brain processes a huge flow of information and regulates the coordinated activity of the body.
Physical exercise has a beneficial effect on the formation and development of all functions of the central nervous system. Even mental activity is impossible without movement. That is why schoolchildren who are constantly involved in physical education and sports better learn the material they study.
Systematic training makes muscles stronger and the whole body more adapted to environmental conditions. Under the influence of muscle loads, the heart rate increases, which leads to improved blood circulation and the heart muscle strengthens.
Constant physical exercise helps to increase the mass of skeletal muscles, strengthen joints, ligaments, and bone growth and development. In a strong, seasoned person, mental and physical performance and resistance to diseases increase.
Flexibility Flexibility is a person’s ability to perform exercises with a maximum range of motion. Flexibility exercises are aimed at developing mobility in all joints, ligaments and tendons. These include bends, turns, rotations, swings, stretching, etc.
