Almost all body movements associated with the simultaneous contraction of the agonist and antagonist muscles on opposite sides of the joints, which is called the coactivation of the agonist and antagonist muscles. Coactivation is controlled by the motor centers of the brain and spinal cord.
The position of each part body, such as arms or legs, is determined by the relative degrees of contraction of the muscle groups of agonists and antagonists. Suppose that the arm or leg should be in the middle position. To do this, the muscles agonists and antagonists are excited approximately to the same extent. Recall that a muscle contracts with more force when lengthening than when shortened: a muscle develops maximum contractile force at its full functional length, and develops almost no force at half its original length. Therefore, an elongated muscle on one side of the joint can contract with much more force than a shorter muscle on the opposite side.
As arm or leg move in the direction of their middle position, the force of contraction of the longer muscle decreases, while the force of contraction of the shorter muscle increases until both forces become equal to each other. At this point, the movement of the arm or leg stops. Thus, by changing the degree of activation of the agonist and antagonist muscles, the nervous system controls the position of the arm or leg.
All muscles of the body are constantly reconstructed adapting to their intended function. Their diameter, length, developed strength, vascular supply and even types of muscle fibers change (to a small extent). This reconstruction process is often carried out quite quickly - within a few weeks. Animal experiments have shown that in some small, active muscles, contractile proteins can be replaced within as little as 2 weeks.
Muscle hypertrophy and atrophy. An increase in total muscle mass is called muscle hypertrophy, and a decrease is called muscle atrophy.
Muscular hypertrophy is almost always the result of an increase in the number of actin and myosin filaments in each muscle fiber, which leads to their enlargement. This is called simple fiber hypertrophy. The degree of hypertrophy increases significantly if the muscle is loaded during contraction. For the development of significant hypertrophy, only a few strong contractions per day for 6-10 weeks are enough.
Mechanism, by which strong contraction leads to hypertrophy is not clear. It is known, however, that with the development of hypertrophy, the synthesis of muscle contractile proteins is sharply accelerated. This contributes to a gradual increase in the number of actin and myosin filaments in myofibrils, the number of which often increases to 50%. It has also been noted that some myofibrils in hypertrophied muscle are themselves split with the formation of new myofibrils, but the importance of this process in normal muscle hypertrophy is still unknown.
Along with the increase in size myofibril enzymatic energy-producing systems are also enhanced. This is especially pronounced in the enzymes for glycolysis, which provides a rapid energy delivery during a powerful short-term muscle contraction.
If in for many weeks the muscle is not used, the rate of decay of contractile proteins in its fibers becomes higher than the rate of their recovery. As a result, muscle atrophy develops.
Muscle Length Adjustment. When muscles are stretched beyond their normal length, another type of hypertrophy develops. This leads to the addition of new sarcomeres at the ends of the muscle fibers where they attach to tendons. It is known that in a newly developing muscle, new sarcomeres can be added very quickly - up to several sarcomeres per minute, which characterizes the possible rate of development of this type of hypertrophy. Conversely, if the muscle consistently remains shorter than normal length, the sarcomeres at the ends of the muscle fibers may actually disappear. Through these processes, muscles are constantly remodeled to be of the appropriate length for proper muscle contraction.
Hyperplasia of muscle fibers. When a muscle develops excessive contraction force (in rare cases), in addition to fiber hypertrophy, their absolute number also increases. This increase in the number of fibers is called hyperplasia. During this process, a linear splitting of the pre-enlarged fibers takes place.
Compensatory-adaptive processes
Lecture No. 14
Adaptation is a concept that is interpreted very broadly and is considered as a property of biosystems aimed at survival in a changed environment.
In pathology, adaptation can manifest itself: 1) atrophy, 2) hypertrophy, 3) organization, 4) metaplasia.
Atrophy is a lifetime decrease in the volume of organs, tissues, cells with a decrease or decrease in their function.
* physiological a) evolutionary - atrophy of the yolk sac
b) involutional (sex glands)
* pathological (reversible process) - general, local.
General - exhaustion, cachexia 1) alimentary, 2) hormonal (pituitary cachexia), 3) debilitating diseases - cancer.
local: 1) dysfunctional - atrophy from inactivity (muscle atrophy after immobilization for a fracture, atrophy of the optic nerve after removal of the eye), 2) from a lack of blood supply - when the lumen is narrowed by atherosclerotic plaques - atrophy of the substance of the brain, myocardiocytes, 3) atrophy from pressure - hydronephrosis - the kidney is enlarged in size, the cortex is thinned, the pelvis and calyces are dilated, filled with urine. Hydrocephalus - expansion of the ventricles of the brain, an increase in the size of the head in violation of the outflow of cerebrospinal fluid, 4) neurotic - due to impaired innervation - with poliomyelitis, the motor neurons of the anterior horns of the spinal cord die and atrophy of the striated muscles develops, 5) as a result of physical and chemical factors - under the influence of irradiation, atrophy of the bone marrow - (severe anemia) and genital organs (infertility).
Hypertrophy- intravital increase in the volume of the organ with an increase in its function.
Reversible process.
1. Neurohumoral hypertrophy (hyperplasia) - in violation of the function of the endocrine glands. An example of endometrial glandular hyperplasia in ovarian dysfunction.
2. Hypertrophic growths - an increase in the size of organs and tissues that occurs with chronic inflammation, impaired lymphatic drainage, with the replacement of muscle tissue with adipose tissue (the so-called false hypertrophy).
Compensatory processes- have a more limited value, they develop in the body of an individual in response to a specific injury, develop in diseases, are staged in nature, The following stages of compensation are distinguished: 1) subcompensation - the stage of urgent compensation (overload stage), 2) the stage of compensation, 3) decompensation - depletion of compensation.
The main morphological manifestation of compensation is hypertrophy.
Types of compensatory hypertrophy
* working - with increased load on the body. Example: left ventricular hypertrophy with high blood pressure, with pyloric stenosis - the muscle is above the constriction in the form of a pulp.
* Vicar (replacement) - in case of death of one of the paired organs (kidneys, lungs). The deficiency of the dead organ is fully compensated.
Regeneration- restoration of structural elements of the tissue to replace the dead. Adaptive process: molecular, subcellular, cellular, tissue, organ.
The philosophical question is what is more important to restore structure or function. In morphology, the principle of unity of structure and function is considered. The function is a more mobile part of this system, it recovers faster, and in some cases without a complete restoration of the structure
(due to intracellular regeneration)
Mechanisms of regeneration
1. Cell hyperplasia (cellular function of regeneration) - cell reproduction - an increase in the number of cells.
2. Intracellular (hypertrophy) - an increase in cell size, with increased cell hyperplasia, reflects the quantitative side of the process, and hypertrophy - qualitative (increased function), however, they are interconnected, because both processes are based on hyperplasia (in one case of cells, in the other - ultrastructures). There are organs that have a predominantly cellular type of regeneration - the epidermis, mucous membranes of the gastrointestinal tract, respiratory tract, and connective tissue. For the liver, kidneys, endocrine glands - a mixed type of regeneration is characteristic. There are organs with a predominantly intracellular mechanism of regeneration - the heart and nerve cells.
Stages of regeneration
Stage I - proliferation class. (cambial, stem, predecessors).
Stage II - differentiation - cell maturation
Regulation
1) Humoral - hormones growth factors, keyons (substances that inhibit cell division and their synthesis), 2) immunological, 3) neurotrophic.
Classification
Regeneration
* Physiological - blood - 2 months, epidermis - 7 days
* Reparative (restorative) - the most significant in pathology - complete, incomplete.
* Pathological - 1) hyporegeneration, 2) hyperregeneration, 3) metaplasia.
Reparative-the most common form of regeneration (restorative) Complete regeneration- develops in tissues and organs that have a cellular mechanism of regeneration - replacement of a defect with a tissue identical to
4 dead. An example is erosion of the epithelium.
Incomplete - replacement of a defect with connective tissue - for organs with an intracellular regeneration mechanism - a scar on the heart after a heart attack, healing of a scar with a stomach ulcer, etc.
The liver is a unique organ; both mechanisms of regeneration are characteristic of it. Complete restoration of the organ, and according to the organ type, is possible with the removal of 2/3 of the organ.
Incomplete regeneration - replacement by a scar when pathological processes occur in the liver - necrosis, injury, inflammation.
With incomplete regeneration, regenerative hypertrophy develops in the cells located along the periphery of the scar. Cells increase in size, the number of ultrastructures increases in them. These changes are compensatory in nature and are aimed at restoring the impaired function.
pathological regeneration- perversion of the regenerative process, violation of the change in the phases of proliferation and differentiation.
1. Hyporegeneration - on the example of wound healing - weak granulations develop, healing does not fit within the allotted time frame, it is delayed. Causes: 1) poor nutrition, 2) insufficient blood supply, 3) beriberi, 4) endocrine disorders. Example: leg ulcers that develop due to lack of blood supply are difficult to heal.
2. Hyperregeneration - excessive - granulations in the wound appear early, quickly close the defect and grow excessively, with the maturation of the connective tissue, a keloid (rough) scar is formed. Such granulations are excised, burned out with liquid nitrogen, because. can lead to disfigurement, dysfunction of the joints.
3. Metaplasia - perverted regeneration within one type of tissue. Refers to precancerous conditions. An example - with chronic bronchitis - metaplasia of the epithelium of the bronchi - a change in a homogeneous glandular epithelium to a stratified squamous non-keratinizing one. The reason is chronic
5 drag. Has an adaptive character.
Regeneration of certain types of tissues
1. Connective tissue. The role of connective tissue regeneration in pathology is very high. Granulation tissue is a kind of “temporary organ” created by the body in pathological conditions to perform the protective and reparative function of connective tissue.
There is an expression that regeneration is born in the course of inflammation, it is this connection between inflammation and restoration that is performed by granulation tissue. There are 3 stages of connective tissue regeneration.
1) Granulation tissue. The process begins with the growth (proliferation) of vascular loops that have a vertical course with respect to the surface. The composition of this tissue includes leukocytes, macrophages, lymphocytes, fibroblasts.
Stage 2 - fibrous connective tissue.
The maturation of fb cells leads to the synthesis of collagen fibers, glycosaminoglycans. At the same time, vascular proliferation stops, cells are destroyed. At this stage, there are much fewer cells, many fibers, fewer vessels.
Stage 3 - scar, coarse fibrous tissue.
Most of the capillaries become empty, recalibration of the vessels develops, only mature connective tissue cells (fibrocytes) remain, collagen fibers occupy the bulk of the tissue. Outcomes: 1) hyalinosis, 2) dystrophic calcification.
2.Bone regeneration -
1. Preliminary connective tissue callus - ingrowth of bone fragments into the area of the defect and hematoma of young mesenchymal elements and vessels (granulation tissue).
2. Preliminary callus - activation and proliferation of osteoblasts in the periosteum and endosteum, randomly located bone beams are formed, maturation.
3. Final callus - due to functional load
6, an ordered structure of the bone callus arises due to the action of osteoclasts.
Complications: 1) false joint - stops at the stage of preliminary bone mazol. 2) exostoses - excessive regeneration.
Regeneration of the nervous system
CNS - intracellular
peripheral nerves. Complete regeneration occurs if the gap is no more than 0.5 mm. Microsurgery - severed hand, finger, head.
When the nerve is transected, the central and peripheral segments are distinguished.
Due to the peripheral section, the Shvalov shell is regenerated, and the axial cylinder disintegrates. And the growth goes towards each other. An axial cylinder grows from the central process, which grows into the peripheral section. The axial cylinder grows 1 mm per day.
It is possible to develop a complication of an amputation neuroma, when the gap is more than 5 mm and the growing axial cylinder does not grow into the peripheral segment. A person may experience “phantom pains” - pain in a remote finger, limb.
Skeletal muscles consist of muscle fibers, m.fiber is a multinuclear arr, the cat has: 1. the plasma membrane has invaginations in the form of transverse tubules) 2. Sarcoplasm reticulum (SPR), which forms a longitudinal stimulus of the tubules 3. myofibrils , the cat embraces the contractile apparatus of the muscles, they are located to each other, while due to the different overlapping, they form A-and I-disks, due to which there is a transverse striation of the entire fiber.
Each myofibril consists of myofilaments, which are thin filaments of the actin protein and thick teites of the mybren protein. Morph. functional. unit of muscle fibers yavl. sarcomere.
Physiological properties of skeletal muscles: 1) excitability (lower than in the nerve fiber, due to the low value of the membrane potential); 2) low conductivity, about 10–13 m/s; 3) refractoriness (takes a longer period of time than that of a nerve fiber); 4) lability; 5) contractility (the ability to shorten or develop tension).
There are two types of contraction: a) isotonic contraction (length changes, tone does not change); b) isometric contraction (the tone changes without changing the length of the fiber). There are single and titanic contractions. Single contractions occur under the action of a single stimulus, and titanic contractions occur in response to a series of nerve impulses; 6) elasticity (the ability to develop stress when stretched).
The mechanism of electrical coupling (which is the basis of contraction) muscle contraction and relaxation is a series of processes that unfold in the following sequence: nerve impulse --> release of acetylcholine by the presynaptic membrane of the neuromuscular synapse --> interaction of acetylcholine with the postsynaptic membrane of the synapse --> occurrence action potential --> electromechanical coupling (conduction of excitation through T-tubules, release of Ca ++ and its effect on the troponin-tropomyosin-actin system) --> formation of transverse bridges and "sliding" of actin filaments along myosin --> decrease in ion concentration Ca ++ due to the work of the calcium pump --> spatial change in the proteins of the contractile system --> relaxation of myofibrils. Energy ATP spends on the 5th step relaxed passively, but it is energy dependent (Ca channels closing energy)
In humans, as in all vertebrates, skeletal muscle fibers have three properties: 1) excitability, i.e. the ability to respond to the stimulus with changes in ion permeability and membrane potential: 2) "conductivity" - the ability to conduct an action potential along the entire fiber: 3) contractility, i.e. the ability to contract or change voltage when excited.
Under natural conditions, excitation and contraction of muscles are caused by nerves. impulses coming to the muscle fibers from the nerve centers. Immediate irritation of the muscle itself is called direct irritation; engine irritation. nerve, leading to a contraction of the muscle innervated by this nerve - an indirect stimulus. Due to the fact that the excitability of muscle tissue is lower than that of nervous tissue, the application of irritating current electrodes is directly to the muscle does not yet provide direct irritation: the current, spreading through the muscle tissue, acts primarily on the end of the motor located in it. nerves and excites them, which leads to muscle contraction.
33. Functioning of skeletal muscles in vivo. motor units. Solitary and tetanic contractions. The reasons for their different strengths according to Helmholtz and in the light of modern ideas.
Depending on the conditions in which muscle contraction occurs, there are two main types of it - isotonic and isometric. Muscle contraction, in which its fibers are shortened, but the tension remains constant, is called isotonic. An isometric contraction is such a contraction in which the muscle cannot shorten if both its ends are fixed motionless. In this case, as the contractile process develops, the tension increases, and the length of the muscle fibers remains unchanged. In natural motor acts, muscle contractions are mixed: even when lifting a constant load, the muscle not only shortens, but also changes its tension due to a real load. motor units
The main morpho-functional elements of the neuromuscular apparatus of skeletal muscles is the motor unit (MU). It includes a motor neuron of the spinal cord with muscle fibers innervated by its axon. Inside the muscle, this axon forms several terminal branches. Each such branch forms a contact - a neuromuscular synapse on a separate muscle fiber. Nerve impulses coming from a motor neuron cause contractions of a certain group of muscle fibers. The motor units of small muscles that carry out racing movements (muscles of the eye, hand) contain a small amount of muscle fibers. In large ones, there are hundreds of times more. All DUs, depending on their functional features, are divided into 3_groups: I. Slow, tireless. They are formed by red muscle fibers, in which there is less myofnbril. The rate of contraction and strength of these fibers are relatively small, but they are not very fatiguable. Therefore, they are referred to as tonic. The regulation of contractions of such fibers is carried out by a small number of motor neurons, the axons of which have few terminal branches. For example, the soleus muscle. N V. Fast, easy to tire. Muscle fibers contain many myofibrils and are called "white". Contract quickly and develop great strength, but tire quickly. Therefore, they are called phasic, Motoneioons of these. abbreviations.
A. Single cut(voltage) occurs when a single electrical or nerve impulse acts on a muscle. The wave of excitation occurs at the site of application of the electrodes for direct stimulation of the muscle or in the region of the neuromuscular junction and from here spreads along the entire muscle fiber. In the isotonic mode, a single contraction of the frog's gastrocnemius muscle begins after a short latent (latent) period - up to 0.01 s, followed by a rise phase (shortening phase) - 0.05 s and a decline phase (relaxation phase) - 0.05-0, 06 p. Usually the muscle is shortened by 5-10% of its original length. As you know, the duration of the excitation wave (AP) of muscle fibers varies, amounting to a value of the order of 1 - 10 ms (taking into account the slowdown of the repolarization phase at its end). Thus, the duration of a single contraction of a muscle fiber following its excitation is many times greater than the duration of AP. The muscle fiber reacts to irritation according to the “all or nothing” rule, i.e. responds to all suprathreshold stimuli with standard PD and standard single contraction. However, the contraction of the whole muscle during its direct stimulation is highly dependent on the strength of stimulation. This is due to the different excitability of muscle fibers and their different distances from irritating electrodes, which leads to an uneven number of activated muscle fibers. At threshold stimulus strength, muscle contraction is barely noticeable because only a small number of fibers are involved in the response. With an increase in the strength of stimulation, the number of excited fibers increases until all fibers are contracted, and then the maximum contraction of the muscle is achieved. Further strengthening of stimuli does not cause an increase in the amplitude of contraction. Under natural conditions, muscle fibers work in the mode of single contractions only at a relatively low frequency of motoneuron impulses, when the intervals between successive APs of motoneurons exceed the duration of a single contraction of the muscle fibers innervated by them. Even before the arrival of the next impulse from the motor neurons, the muscle fibers have time to completely relax. A new contraction occurs after complete relaxation of the muscle fibers. This mode of operation causes a slight fatigue of muscle fibers. At the same time, they develop relatively little stress.
B. tetanic contraction is a prolonged continuous contraction of skeletal muscles. It is based on the phenomenon of summation of single muscle contractions. When applied to a muscle fiber or a whole muscle of two quickly following each other irritations, the resulting contraction will have a large amplitude. The contractile effects caused by the first and second stimuli seem to add up, there is a summation, or superposition, of contractions, since the actin and myosin filaments additionally slide relative to each other. At the same time, muscle fibers that have not contracted before can be involved in contraction if the first stimulus caused them to subthreshold depolarization, and the second increases it to a critical value. When summation is obtained in a single fiber, it is important that the second stimulation be applied after the disappearance of AP, i.e. after the refractory period. Naturally, the superposition of contractions is also observed during stimulation of the motor nerve, when the interval between stimuli is shorter than the entire duration of the contractile response, as a result of which the contractions merge. At relatively low frequencies, serrated tetanus sets in, and at high frequencies, smooth tetanus occurs (Fig. 6.4). Their amplitude is greater than the maximum single contraction. The tension developed by muscle fibers during smooth tetanus is usually 2-4 times greater than during a single contraction. The mode of tetanic contraction of muscle fibers, in contrast to the mode of single contractions, causes their fatigue faster and therefore cannot be maintained for a long time. Due to the shortening or complete absence of the relaxation phase, muscle fibers do not have time to restore the energy resources expended in the shortening phase. The contraction of muscle fibers in the tetanic mode, from an energy point of view, occurs "in debt".
As it turned out, the amplitude of smooth tetanus varies widely depending on the frequency of nerve stimulation. At some optimal (sufficiently high) stimulation frequency, the smooth tetanus amplitude becomes the highest. Such a smooth tetanus is called the optimum. With a further increase in the frequency of nerve stimulation, a block in the conduction of excitation in the neuromuscular synapses develops, leading to muscle relaxation during nerve stimulation - the Vvedensky pessimum. The frequency of nerve stimulation at which a pessimum is observed is called the pessimal (see Fig. 6.4).
In the experiment, it is easily found that the amplitude of muscle contraction, reduced during pessimal rhythmic stimulation of the nerve, instantly increases when the frequency of stimulation returns from pessimal to optimal. This observation is good evidence that pessimal muscle relaxation is not a consequence of fatigue, depletion of energy-intensive compounds, but is a consequence of special relationships that develop at the level of post- and presynaptic structures of the neuromuscular synapse. Pessimum Vvedensky can also be obtained with direct, but more frequent muscle stimulation (about 200 imp/s).
34. Work and muscle strength. Muscle fatigue and its causes in natural and laboratory conditions. Active recreation according to I.M. Sechenov.
There are the following modes of muscle contraction: 1. Isotonic contractions. The length of the muscle decreases, but the tone does not change. They are not involved in the motor functions of the body. 2. isometric contractions. The length of the muscle does not change, but the tone increases. Underlying static work. For example, while maintaining body posture. 3. Auxotonic contractions. The length and tone of the muscle also change. They are used to move the body. other motor acts.
Max. muscle strength is the value of max. tension, the cat can develop the muscle. It depends on the structure of the muscle, its function. condition, initial length, gender, age, degree of training. h-ka. Depending on the structure, they distinguish muscles with parallel fibers, feathery. These types of muscles have a different area of the transverse physiological. sections. The largest area of the transverse fiziol. section and strength, in pennate muscles. The smallest - muscles with parallel. disposition of fibers.
With moderate stretch. muscle strength of its contraction age., but with overstretching. - reduce With moderate heating, it also increases, and decreases with cooling. Muscle strength decreases with fatigue. metabolism, etc. Max. strength different. muscle groups determined by dynamometers.
To compare the strengths of different muscles, their specific or absolute strength is determined. It is equal to max. divided by sq. see cross-sectional area of the muscle. The specific strength of the human gastrocnemius muscle is u.2 kg cm2. triceps - 16.8 kg / cm2, chewing - 10 kg / cm 2. muscle work is divided into dynamic and static. Dynamic is performed when moving the load. During dynamic work, the length of the muscle and its tension change. Therefore, the muscle works in auxotic mode. During static work, the movement of the load does not occur, i.e. muscle works in isometric mode. Dynamic work is equal to the product of the weight of the load by the height of its rise or the amount of shortening of the muscle (A \u003d P * h)
Work is measured in kg * M, joules. The dependence of the magnitude of work on the load obeys the law of average loads. When the load increases, the work of the muscles initially increases. At medium loads, it becomes maximum. If the increase in load continues, then the work decreases. The same effect on the magnitude of the work has its rhythm. Maximum muscle work is carried out at an average rhythm. Of particular importance in calculating the magnitude of the workload is the definition of muscle power. This is the work done per unit of time (P = A * T). Tue
Muscle fatigue Fatigue is a temporary decrease in the performance of the mouse as a result of work. Fatigue of an isolated muscle can be caused by its rhythmic stimulation (abbreviated force). The higher the frequency, the strength of irritation, the magnitude of the load, the faster the fatigue develops. With fatigue, the curve of a single contraction changes significantly. The duration of the latent period, the period of shortening, and especially the period of relaxation increases, but decreases. amplitude. The stronger the fatigue of the muscle, the longer the duration of these periods. In some cases, complete relaxation does not occur, contracture develops (a condition of involuntary prolonged muscle contraction.) Work muscle fatigue is examined using ergography
Sechenov called rest with the inclusion of other muscle groups active. It has now been established that motor fatigue is associated with inhibition of the corresponding nerve centers, as a result of metabolic processes in neurons, deterioration in the synthesis of neurotransmitters and inhibition of synaptic transmission.
35. Hypertrophy and muscle atrophy. Hypodynamia, mechanisms of adaptation. Fatigue of the body and its prevention
Muscle hypertrophy - increased. muscle cytoplasm masses. fibers and the content of myofibrils in them, this leads to an increase in each fiber in diameter. (+ active synthesis of nucleic acid and proteins and increased soda-I in-in, which supply energy, which is used during muscle contraction - creatine phosphate and adenosine triphosphate, as well as glycogen. (strength and speed of contraction . increase)
Muscle atrophy develops when the muscles do not perform a normal load for a long time. the diameter of muscle fibers and the content of proteins, ATP, glycogen, and other contractile substances for activity decrease. After the resumption of work, muscle atrophy gradually disappears. (Another type - with damage to the motor nerve)
Hypokinesia is a complex of motor disorders (decrease in motor activity and slowness of movements) that develop with lesions of the central nervous system. Restriction of mobility due to lifestyle, characteristics of professional activity, bed rest during the period of illness, immobilization (gypsum bandages, skeletal traction) and accompanied by a lack of muscle load, is called hypodynamia.
36. Smooth muscles, their functions, features of contraction and excitation. Smooth muscle irritants.
Physiological features of smooth muscles. 1) excitability (lower than in the nerve fiber, which is explained by the low value of the membrane potential); 2) low conductivity, about 10–13 m/s; 3) refractoriness (takes a longer period of time than that of a nerve fiber); 4) lability; 5) contractility (the ability to shorten or develop tension).
There are two types of reduction: a) isotonic contraction (length changes, tone does not change); b) isometric contraction (the tone changes without changing the length of the fiber). There are single and titanic contractions. Single contractions occur under the action of a single stimulus, and titanic contractions occur in response to a series of nerve impulses; 6) elasticity (the ability to develop stress when stretched).
Smooth muscles have the same physiological properties as skeletal muscles, but they also have their own characteristics: 1) unstable membrane potential, which maintains the muscles in a state of constant partial contraction - tone; 2) spontaneous automatic activity; 3) contraction in response to stretching; 4) plasticity (decrease in stretching with increasing stretching); 5) high sensitivity to chemicals.
Smooth muscles are present in the walls of the large. digestive organs, vessels, excretory ducts of urinary glands. systems. They are unproductive. and provide peristalsis org-in the digester. and urinary sys-we, support. vascular tone. Unlike skeletal, smooth muscle cells are more often spindle-shaped. shape and small size, not having transverse blackness. The latter is due to the fact that the contractile apparatus does not have an ordered structure. Myofibrils consist of thin filaments of actin, which go in various directions and are attached. to different parts of the sarcolemma. Myosin protofibrils are located next to actin fibrils. The elements of the SPR do not form a system of tubules. Separate muscle cells are connected to each other by contacts with a low electr. resist. - nexus, which will provide. distribution of the excitation throughout the smooth mouse. p-re. Let's excite. and we conduct. smooth muscle is lower than skeletal muscle. MP \u003d 40-60 mV, because the MMC membrane has a relatively high permeability for Na ions. Moreover, in many smooth muscles, MP is not constant. It is periodically reduced. and return again. to the original level. Such oscillations are called slow waves (SW). When the top of Mv reaches the KUD, PDs start to be generated on it. MV and PD are conducted through smooth muscles at a speed of only 5 to 50 cm/sec. Such smooth muscles are called spontaneously active, i.e. they are automatic. For example, due to such an act, intestinal peristalsis occurs. The pacemakers of intestinal peristalsis are located in the initial sections of the corresponding intestines.
The generation of APs in MMCs is due to the entry of Ca ions into them. The mechanisms of electromechanical coupling are also different. The contraction develops due to Ca entering the cell during PD. The most important cellular protein, calmodulin, mediates the relationship of Ca with the shortening of myofibrils.
The contraction curve is also different. The latent period, the period of shortening, and especially relaxation, is much longer than that of skeletal muscles. The contraction lasts a few seconds. Smooth muscles, unlike skeletal muscles, are characterized by the phenomenon of plastic tone. This ability is in a state of reduction for a long time without significant energy consumption and fatigue. Thanks to this property, the shape of the internal organs and vascular tone are maintained. In addition, smooth muscle cells themselves are stretch receptors. When they are stretched, APs begin to be generated, which leads to a reduction in the SMC. This phenomenon is called: myogenic mechanism of regulation of contractile activity
If you have already tried to figure out how muscles grow, then most likely you are already confused in incomprehensible terms, and many sources give conflicting information.
I will try to tell in a simple and accessible form what's what - what types of muscle fibers exist, how they "turn on", what types of hypertrophy exist, what trainings can achieve muscle growth and what it depends on.
Muscle structure is very complex, so we're going to simplify a lot. The article was prepared specifically for beginners, we will not dig deep.
The structure and composition of muscles.
It should be understood that muscles are made up of several components. Protein only makes up 20-25% of the total muscle mass. The rest is the muscle fiber supply system, which includes: glycogen (carbohydrate storage), water, minerals, creatine phosphate, mitochondria (for energy production), capillaries, some fat in the form of intramuscular triglycerides, etc., that is, in fact, muscles 70-80% are water.
Types of hypertrophy.
Only if we are talking about muscle growth is it customary to use the term hypertrophy. Hypertrophy is an increase in the size of the muscle fibers themselves. There is also the term "Hyperplasia" - an increase in the number of muscle fibers, but we will not talk about it.
An interesting, and very important point for us - there are two types of hypertrophy:
Sarcoplasmic.
Myofibrillar.
Myofibrillar hypertrophy is an increase in the size of the fibers themselves, their protein component. This is "True" muscle growth. To start this type of hypertrophy, it is necessary to create a powerful stimulus of great effort (strength training. Protein synthesis is a rather energy-consuming process, so it is very important not only to create a stimulus with strength training, but also to properly organize nutrition.
Sarcoplasmic hypertrophy is an increase in the volume of everything else that makes up the muscle: glycogen, water, minerals, etc. The main stimulus is the depletion of these energy resources (especially glycogen. This causes the cell to replenish glycogen (and therefore water, since glycogen is stored in the body in the "Wet" form, retaining 3-4 g of water per gram) and replenish them in excess, so that the muscles appear larger.Regular high-rep training also increases the capillary network, mitochondria and all other non-contractile elements, which additionally visually increase muscle size.
Types of muscle fibers.
There are two main types of muscle fibers - type I fibers and type II fibers (often intermediate types of fibers are also distinguished, but we will simplify.
Type I fibers are called slow muscle fibers (SMF) or red fibers, type II fibers are called fast muscle fibers (bmw) or white fibers.
But it should be understood that the very words "Fast" and "slow" fibers refer to the speed at which muscle fibers can generate force. MMV are reduced in 0.1 seconds, and BMW in 0.05. But this does not mean at all that the speed of the exercise affects which fibers will be included in the work. That is why the terms BMW and MMV bring confusion and misunderstanding of the very essence of the work of the muscular system.
The classification into slow and fast fibers is based on the activity of atphase (an enzyme necessary for muscle contraction. The higher the activity, the more powerful the contraction. In slow fibers, the atphase rate is much lower, that's all.
Fibers also differ in the type of energy supply: oxidative and glycolytic. Oxidative - means that it works by oxidizing fatty acids and glucose and oxygen is needed for their work, and glycolytic ones work on anaerobic (without oxygen access) glycolysis. Oxidative fibers are more enduring and least strong, while glycolytic fibers have an extremely short duration of work (about a minute), but have the greatest power and contraction force.
motor units.
In general, muscles are not tensed by specific individual fibers. The muscular system uses the so-called motor units (de) - several muscle fibers that are innervated by one motor neuron. Accordingly, de is divided into high-threshold motor units (vpde) and low-threshold motor units (npde. They also correspond to BMW and MMV.
They have a motor neuron with a small cell body that innervates 300 to 800 muscle fibers. Npde have a low activation threshold, so they are included in the work first.
They are innervated by motor neurons that have a large body and have a high input resistance, so they are activated last.
With the development of effort from weak to strong, a stable order of recruitment ("Inclusion") is observed de: first npde --.
Sarcoplasmic muscle hypertrophy. Not all muscles are the same
One of the main problems in training strength athletes (American football players, baseball players, basketball players, wrestlers and even powerlifters), in my opinion, is too much emphasis on exercises with 10-15 reps per set. This kind of training has a place in the preparation of athletes, but it needs to be given less attention. For example, linemen (in American football, these are big guys who stand on the line and have to break through / prevent breaking through to point guards) need to gain mass so that they are not kicked all over the field. The high rep "bodybuilding" approach can be very helpful during the season to prevent muscle loss and also to rebuild lost mass after the season is over. There is also scientific evidence that large muscles are easier to make strong in the future if you start training for strength indicators. The main thing to remember is that this type of hypertrophy has nothing to do with explosive strength and movements such as punching, running, throwing, jumping, or maximizing strength in one movement. This is why bodybuilders who work primarily on type IIA fibers and gain growth in non-contractile muscle components (sarcoplasmic volume, capillary density and mitochondrial growth) are not the fastest and strongest athletes in the world. And this is despite the fact that they have, on average, more muscle than any other athlete! I believe that in such hypertrophy form prevails over function.
Muscular hypertrophy is an increase in muscle mass, as well as their cross-sectional area. This happens when the overload increases rapidly. The heart and skeletal muscles can get used to the constant increase in workload. Muscle tissue cells begin to more effectively transfer force through the tendons to the bones. The overall picture of this process is very complex and is still not fully understood by doctors.
In muscle hypertrophy, the mass and cross-sectional area of the muscles is due to an increase in the size of individual muscle fibers, while their length remains the same.
Each skeletal muscle performs two functions: contracting (to move the body), stabilizing (to maintain position). It can contract with varying amounts of tension to do the job. During hypertrophy, various variable stresses occur in the muscle, which forces it to adapt. It does this by increasing the size as well as the number of contractile proteins that make up the myofibrils within each fiber. This contributes to an increase in individual fibers and their strength.
Hypertrophy changes:
- speed of muscle contraction;
- maximum work force;
- resistance to fatigue.
The nature of adaptation can be different depending on different systems of response to loads.
Hypertrophy can be called a combination of local and peripheral events that are coordinated with each other. The main regulatory signals for them are mechanical, hormonal, nervous and metabolic factors.
Types of hypertrophy
The main types of hypertrophy:
- myofibrillar (when the muscles increase due to the growth and increase in the number of myofibrils. They fit more densely in the fiber. More often this type of hypertrophy occurs with type IIB fast fibers).
- sarcoplasmic (when the muscles increase due to an increase in the volume of the sarcoplasm, that is, the part that does not contract. The amount of mitochondria, glycogen, creatine phosphate, etc. increases in the fibers. More often this type occurs with slow type I muscles, as well as fast oxidative types IIA).
Mechanisms of hypertrophy
Scientists put forward several theories that explain the mechanisms of myofibrillar-type hypertrophy. These hypotheses include:
- acidosis;
- hypoxia;
- Mechanical damage.
The acidosis hypothesis suggests that the main stimulus that starts the process of hypertrophy is the accumulation of lactic acid in the muscle. It damages the sarcolemma of the muscle fibers and the membranes of the organelles. At the same time, calcium ions appear in the fiber, which activate proteolytic enzymes that break down proteins.
The hypoxia hypothesis says that the main reason is the lack of oxygen for some time. This happens when you train with a lot of weight. The lack of oxygen, and then active saturation with it, damages the fiber membranes, which entails saturation with calcium ions, etc.
The hypothesis of mechanical damage suggests that the main factor is damage to contractile proteins, which occurs with strong muscle tension.
Androgens play an important role in the growth of muscle volume. Women also produce them, but to a lesser extent. The more of these hormones the body produces, the faster the muscles grow.
Hypertrophy Factors
There are several prerequisites without which this process cannot begin:
- synthesis of contractile proteins;
- ribonucleic acid;
- hyperplasia (an increase in the number of fibers);
- androgenic anabolic steroids.
Degree score
The degree of hypertrophy can be assessed by measuring its mass and volume. These days, this can be done with a CT or MRI. The specialist must evaluate the change in the maximum value of the cross section of the muscle.
Skeletal muscle hypertrophy. Workout type
Functional hypertrophy of human skeletal muscle depends on the type of training, which also affects the work of either type I or II fibers. The simple conclusion from this is that light, low-intensity bodyweight training will include most type I work, as a result of which, the cross-sectional area of \u200b\u200bthe muscle remains practically unchanged. Strength, high-speed training with large weights includes type II work, which significantly increases the cross-sectional area.
In addition, there are two types of hypertrophy:
- Myofibrillar;
- Sarcoplasmic.
In order not to go into the details of the structure, let's just clarify that the sarcoplasm is the liquid content around the fibers, the myofibrils are thin threads that run along the muscle fiber. You can see the difference more clearly in the picture.
So - the type of training also affects the type of muscle growth. Low-intensity long-term training leads to sarcoplasmic hypertrophy, i.e. increase the volume of the sarcoplasm, in which the amount of glycogen and creatine phosphate increases. This increases endurance and allows you to make the next workout longer. So, for example, hypertrophy occurs in long-distance runners. Myofibrillar hypertrophy occurs under the influence of strength training and leads to an increase in the myofibrils themselves and, accordingly, in the cross-sectional area.
However, in its pure form, neither the first nor the second is found. There is always a mixed type. But in strength training, the second prevails, in aerobic - the first.
There are two types of muscle hypertrophy - true and false. False muscle hypertrophy is a negative process when an external increase in muscle mass occurs due to an increase in body fat, obesity.
True muscle hypertrophy is the result that fans of strength sports strive for, characterized by an increase in muscle cells and muscle volume - both in general and in individual muscle groups.
Such muscle growth is of two types - myofibrillar and antispasmodic.
Knowledge is a tool to achieve results. Knowing what hypertrophy is and how to use the biological process to improve the body will allow you to achieve high performance, acquire excellent muscles both in the gym and in independent training at home.
Myofibrillar type
Myofibrillar-type muscle hypertrophy, characterized by dry muscles, is achieved by an increase in the number, size and density of the myofibrils that make up the contractile tissue.
The increase in such muscle structures contributes to an increase in strength and power. Myofibrillar type hypertrophy is used in powerlifting, weightlifting and arm wrestling.
The myofibrillar type of muscle hypertrophy is typical for fast fibers that perform high-speed actions, powerful, "explosive" but quickly tired.
When performing exercises aimed at switching on the mechanism of this type of hypertrophy, the muscles must be given rest between the performed approaches, lasting from 1 to 3 minutes.
For muscle growth according to the myofibrillar type, it is recommended to train with sports equipment of high weight and a low number of repetitions. The duration of the workout, as a rule, does not exceed an hour and is built so that the muscle groups receive rest for.
In order for the muscles not to adapt to the loads, the training plan should include training with an increase in the number of approaches, using lighter sports equipment.
Sarcoplasmic type
Sarcoplasmic muscle hypertrophy, which is characterized by voluminous but less dense muscles, is achieved by an increase in the nutrient fluid surrounding the muscle fibers.
Muscle growth occurs due to metabolic reactions occurring in muscle cells and thickening of the capillary network of muscles that occur during exercise.
Muscle hypertrophy of the sarcoplasmic type involves slow, low-speed muscle fibers capable of performing long-term movements. Quite insignificant, but overall endurance and muscle relief increase.
This type of training is performed with light and medium-weight sports equipment and can last from one and a half to two hours. For classes, they are carried out at a high pace, using a relatively large number of approaches (up to 12) and a short rest between repetitions.
For muscle growth, their useful, true hypertrophy, there are certain recommendations:
- The use of two types of loads when performing an exercise - with a high and low number of repetitions.
- Periodic change of training programs. As a rule, one training program is performed for no more than two months.
- Building training according to an accentuated type aimed at one muscle group.
- Gradual increase in the weight of sports equipment.
- A prerequisite for muscle growth is high-quality nutrition, which should not only be high in calories, but also contain the required amount of proteins, fats, vitamins and minerals.
The fulfillment of simple conditions will allow you to develop high-quality muscles without the problems of excessive overloads and with pleasure.
What is Sarcoplasmic Hypertrophy?
Myofibrillar hypertrophy of muscle fibers - an increase in the volume of muscle fibers due to an increase in the volume of myofibrils. ... Sarcoplasmic hypertrophy of muscle fibers - an increase in the volume of muscle fibers due to a predominant increase in the volume of the sarcoplasm, i.e., their non-contractile part.
Etiological factors in these patients were: one-sided type of chewing, trauma during sports competitions, boxing. For some, this disease began gradually, imperceptibly, the compression of the jaws gradually increased. For the final diagnosis in patients on the area of the convex hypertrophied muscle, we apply a layer of barium and perform X-ray cinematography in a direct projection, r. full face, and the patient was asked to squeeze and unclench the dentition. With muscle hypertrophy, swelling of the cheek increases sharply with compression and noticeably decreases with unclenching of the jaws.
With this pathology, a plastic mouth guard was made for the entire dentition of the lower jaw with an increase in bite by 3.0 mm. Muscle relaxants (mydocalm. sonapaks) were prescribed under the control of electromyography. Selective electromyostimulation of weakened muscle groups was carried out, the patient was recommended to eat on the opposite side.
Rice. 118. Patient K., 45 years old. Diagnosis: parafunction of the muscles that lift the lower jaw, occlusal-articulation dysfunctional TMJ syndrome.
A - there is a generalized increased abrasion of the teeth of the lower jaw.
B - increased abrasion of the upper frontal teeth.
C - a patient after prosthetics of teeth with the creation of a dense fissure-tubercular contact of all teeth. Explanation in the text.
Treatment of patients with unilateral hypertonicity of the lateral pterygoid muscle
At the beginning of treatment for a month, the patients were prescribed myogymnastics with the mixing of the lower jaw to the midline of the linden and even a little more. In this position of the jaw, the patients made vertical movements 3 times a day for 15 minutes during
- x weeks. Then an apparatus with a lateral inclined plane was made. Treatment was carried out for 4-5 months.
In addition to orthopedic treatment, patients were prescribed massage in the area of the temporal and masticatory muscles proper. Electrophoresis with 5% potassium iodide solution in the TMJ area. After treatment, all pathological symptoms were eliminated. The movements of the lower jaw became smooth, without mixing to the side.
Treatment of patients with bruxism and lateral shift of another etiology was carried out with a plate with an occlusal patch and an inclined plane.
Working muscle hypertrophy and inactivity atrophy
Systematic intensive work of the muscle leads to an increase in the mass of muscle tissue. This phenomenon is called working muscle hypertrophy. Hypertrophy is based on an increase in the mass of the protoplasm of muscle fibers, leading to their thickening. This increases the content of proteins and glycogen, as well as substances that deliver energy used in muscle contraction - adenosine triphosphate and creatine phosphate.
Apparently, in connection with this, the strength and speed of contraction of a hypertrophied muscle is higher than that of a non-hypertrophied one.
The increase in muscle mass in trained people, in whom many muscles are hypertrophied, leads to the fact that the musculature of the body can be 50% of body weight (instead of the usual 35-40%).
Hypertrophy develops if a person daily performs muscular work for a long time that requires a lot of stress (strength load). Muscular work performed without much effort, even if it lasts a very long time, does not lead to muscle hypertrophy.
The opposite of working hypertrophy is muscle atrophy from inactivity. It develops in all cases when the muscle for some reason loses the ability to perform its normal work. This happens, for example, with prolonged immobilization of a limb in a plaster cast, with a patient staying in bed for a long time, with transection of a tendon, as a result of which the muscle ceases to work against the load, etc.
With atrophy, the diameter of muscle fibers and the content of contractile proteins, glycogen, ATP and other substances important for contractile activity in them fall sharply.
With the resumption of normal muscle work, atrophy gradually disappears.
A special type of muscle atrophy is observed during muscle denervation, i.e., after the transection of its motor nerve.
What is cardiac hypertrophy?
HYPERTROPHY OF THE HEART - an increase in the volume of the heart muscle due to the thickening of the wall of the ventricles (the muscle fibers thicken and the size of their nuclei increases). ... In athletes, the muscle of the left and, to a lesser extent, the right ventricle of the heart hypertrophies.
Human skeletal muscle hypertrophy. INTRODUCTION
Myofibrillar hypertrophy is the adaptation of human skeletal muscles to power loads when the training process is aimed at increasing their volume or strength. It has been established that with this type of hypertrophy, the number and volume of myofibrils, the main elements of the muscle fiber, increase.
The aim of the study was to develop a concept describing the mechanisms of myofibrillar hypertrophy of human skeletal muscles under the influence of force-oriented loads.
Muscle atrophy. Causes of muscle atrophy
Primary muscle atrophy is caused by damage to the muscle itself. The cause of the disease in this case may be unfavorable heredity, which is expressed in metabolic disorders in the form of a congenital defect in muscle enzymes or high permeability of cell membranes. Environmental factors that provoke the onset of the pathological process also have a significant impact. These include physical overstrain, infectious process, trauma. The most pronounced primary muscle atrophy in myopathy.
The cause of muscle atrophy can be an injury to the nerve trunks, an infectious process that occurs with damage to the motor cells of the spinal cord, such as poliomyelitis and polio-like diseases.
Sometimes the pathological process is hereditary. In this case, the distal extremities are affected, and the process itself proceeds more slowly and is of a benign nature.
In the etiology of the disease, the following factors are distinguished: malignant tumors, paralysis of the spinal cord or peripheral nerves. Often, muscle atrophy develops against the background of various injuries, starvation, intoxication, as a result of a slowdown in metabolic processes as the body ages, prolonged motor inactivity for any reason, as a consequence of chronic diseases.
If the spinal cord and large nerve trunks are affected, neuropathic muscle atrophy develops. With thrombosis of large vessels or impaired blood flow in muscle tissue as a result of mechanical or pathological damage, an ischemic form develops. The cause of the functional form is absolute, often partial motor inactivity due to pathological processes in the body - arthritis. poliomyelitis and poliomyelitis-like diseases.
Throughout his life, a person experiences various physical loads. It can be both professional strength exercises, and simply related loads that occur in various life situations.
During physical exertion, the muscles that are involved in the process of work increase. This happens due to an increase in the fibers that make up the muscle. may be the entire length of the muscle, and may be shorter. The muscle fiber consists of a large number of contractile elements - myofibrils. Inside each element are even smaller elements - myofiaments actin and myosin. And due to these elements, muscle contraction occurs.
With regular weight lifting, muscle fibers increase, this will be muscle hypertrophy.
Muscle hypertrophy - an increase due to the "growth" of muscle fibers.
Most often, muscle hypertrophy is present in athletes involved in bodybuilding. Since this sport is aimed at improving your body with the help of power loads, high-calorie nutrition and taking various anabolic drugs. As a result, a pronounced muscle relief is formed on the body, that is, muscle hypertrophy occurs.
Processes that occur in muscles during exercise
The basis of the structure of the human body is protein, it is present in all its tissues. Therefore, changes in muscle tissue depend on the synthesis and catabolism of protein in the tissue.
With constant physical activity, skeletal muscle hypertrophy occurs. When the body experiences stress, the content in the corresponding muscles increases. However, as it has been scientifically established, during physical impacts on the body, protein synthesis stops, and catabolism is activated in the first minutes of the recovery process. Thus, muscle hypertrophy occurs due to the activation of protein synthesis, and not due to a decrease in the intensity of protein breakdown at a constant level of protein synthesis intensity.
Skeletal muscle hypertrophy
Human muscle tissue performs motor functions, it forms skeletal muscles. The main task performed by skeletal muscles is contractility, which occurs due to a change in the length of the muscle when exposed to nerve impulses. Using his muscles, a person can "move". Each muscle performs "its" specific action, it can only work in one specific direction when acting on a joint. To ensure the movement of the joint around its axis, a pair of muscles is involved, present on both sides in relation to the joint.
Determines the number and thickness of fibers that are present in a given muscle. They make up the anatomical diameter of the muscle (the area of the transverse section of the muscle, made perpendicular to its length).
There is also such an indicator as the physiological diameter (cross section of the muscle, perpendicular to its fibers).
The value of the physiological diameter affects the strength of the muscle. The larger the physiological diameter, the greater the force inherent in the muscle.
During physical exertion, the diameter of the muscle increases, this is called working muscle hypertrophy.
Working muscle hypertrophy is present when there is an increase in the volume of muscle fibers. With a strong thickening of the fibers, splitting into several new fibers with a common tendon can occur. Working hypertrophy occurs in healthy people with enhanced function of a human tissue or organ. For example, this is human skeletal muscle hypertrophy.
Causes of muscle hypertrophy
Muscle hypertrophy, in most cases, is caused by regular physical activity. However, the amount of calories consumed also affects the increase in muscle mass. If there are not enough calories, a large amount of muscle cannot be achieved.
Concomitant with the achievement of the required muscle volume, that is, there is muscle hypertrophy, the reasons based on the following principles:
- A constant load is needed on all types of muscles, the volume of which needs to be increased.
- The loading time is selected individually. Don't stick to standards. It is necessary to do as much as the body allows, but not to the point of complete exhaustion.
- Do not cause exhaustion of the nervous system, work with concentration, calmly and judiciously.
- At the initial stages of training, muscle pain may appear, but this should not be an excuse to stop exercising.
A complete and balanced diet, plenty of fluids should also be present to maintain the body's water balance.
Increase in masticatory muscles
Due to the "extra" movements of the jaw, hypertrophy of the masticatory muscles may appear. a person is pressed against the top due to the masticatory muscles. They consist of two parts and are located on both sides of the jaw. The muscle begins at the lower edge of the zygomatic arch and ends at the outer surface of the lower branch.
Hypertrophy of the chewing muscles causes a violation in the visual harmonious combination of the upper and lower parts of the face, and also causes pain in the chewing muscles. The face becomes "square" or extended downwards. Muscle hypertrophy occurs due to an increase in the load on them.
Hypertrophy of masticatory muscles can provoke:
- bruxism - grinding of teeth;
- constantly clenched jaws, up to the erasure of teeth;
- pain in the chewing muscles.
Correction of masticatory muscles
With hypertrophy of the chewing muscles, a disproportion of facial features appears in a person. In this case, there may also be a constant pain syndrome in the jaw area. To correct this imbalance, a person needs to contact a specialist to receive medical treatment. In order for muscle hypertrophy to pass, treatment must be started on time.
During treatment, a special drug is injected into the masticatory muscle, in three to four places, which relaxes the muscle and causes local muscle relaxation. After a few days, the effect is visible, which will last about six months.
Hypertrophy of the heart muscle
There are cases when there is a pathological increase in the heart, this is mainly due to an increase in the thickness of the heart muscle - myocardium.
Hypertrophy of the left side of the heart is more common than that of the right side.
Hypertrophy of the heart can appear with:
- congenital or acquired heart defects;
- hypertension;
- metabolic disorders, including obesity;
- sharp loads when a sedentary lifestyle is led.
Symptoms of cardiac muscle hypertrophy
Slight hypertrophy of the heart muscle does not cause any changes in a person's well-being and may go unnoticed. The higher the stage of the disease, the more pronounced the symptoms of the disease. One of the best options for diagnosing the disease is an ultrasound of the heart.
The presence of this disease can be assumed by the presence of such symptoms:
- hard to breathe, breathing is difficult;
- pain in the chest;
- fast fatiguability;
- unstable heart rate.
Increased pressure can provoke ventricular hypertrophy. The heart begins to work faster, the blood in the heart begins to press harder on the walls, thereby expanding and reducing the elasticity of the walls. This leads to the impossibility of the heart to work in the same mode.
Treatment of cardiac hypertrophy
At the initial stage, cardiac hypertrophy is amenable to drug treatment. Diagnosis is carried out in order to identify the cause that provoked the development of hypertrophy, and its elimination begins. If, for example, the disease has developed due to a sedentary lifestyle and excess weight, then a person is prescribed small physical activity and his diet is adjusted. Products are introduced in accordance with the principles of healthy eating.
If ventricular hypertrophy has reached a large size, surgical intervention is performed and the hypertrophied area is removed.
Amyotrophy
Hypertrophy and muscle atrophy are concepts that are opposite in meaning. If hypertrophy means an increase in muscle mass, then atrophy means its decrease. The fibers that make up the muscle that do not receive a load for a long time become thinner, their number decreases and, in severe cases, may disappear altogether.
Muscle atrophy can be caused by various negative processes in the human body, both hereditary and acquired. It could be, for example:
- metabolic disease;
- a consequence of endocrine diseases;
- complication after an infectious disease;
- intoxication of the body;
- enzyme deficiency;
- prolonged postoperative rest of the muscles.
Treatment of muscle atrophy
The effectiveness of treatment depends on the stage of the disease. If the changes in the muscles are significant, it will not be possible to fully restore them. The cause that caused muscle atrophy is diagnosed, and appropriate medication is prescribed. In addition to drug treatment, it is definitely recommended:
- physiotherapy;
- physiotherapy;
- electrotherapy.
To keep the muscles in good shape, a massage is prescribed, which should be done regularly.
Treatment is aimed at stopping the destructive actions in the muscles, relieving symptoms and improving metabolic processes in the body.
Be sure to have a nutritious diet containing all the necessary vitamin elements.
Conclusion
Thus, it can be concluded that in order to obtain hypertrophy of skeletal muscles, it is necessary to apply significant physical effort. If this is done to achieve a beautiful body with a pronounced muscle mass, then the person will be required to perform regular strength exercises. At the same time, his diet should be built on the principles of proper nutrition.
However, there is a possibility of getting unwanted muscle hypertrophy, which poses a threat to human health, this is: hypertrophy of the heart muscle and masticatory muscles. In most cases, the appearance of these diseases is associated with deviations and disorders of the human body. Therefore, timely diagnosis and control over one's health is necessary to prevent the onset and development of the disease.
A healthy lifestyle and proper nutrition will help a person stay in good physical shape and avoid possible health problems.