Physiological changes in the human
Changes in the human body under the influence of physical activity
Training of fitness of a person and his body:
The beauty and power of a trained body has always attracted painters and sculptors. This was apparent already in rock cave paintings of our ancestors who have attained perfection in the frescoes of ancient Greece, the sculptures of Michelangelo. At the same time is not always the fitness
of the person is accompanied by an increase stamina and records in professional sport, the body often paid a high price.
The fitness of the human body is the ability to perform heavy physical exertion is usually observed in people whose lifestyle or profession are associated with intense muscular activity: the loggers, miners, riggers, athletes. Trained body, adapted to physical exercise, are not only able to perform intense muscular work, but also is more resistant to situations that cause illness, emotional stress, environmental influences.
Features of a trained body man:
There are two main features of a trained body man accustomed to more physical activity. The first feature is the ability to perform muscular work such duration or intensity that is beyond the power untrained body. Not accustomed to physical activity of a person is not able to run a marathon or lift weights with a weight far exceeding his own. The second feature is more effective functioning of physiological systems at rest and during moderate load and at maximum load — ability to achieve this level of functioning, which is impossible for an untrained body.
So, at rest from constantly performing strenuous exercise person’s heart rate may be as low as 30-50 beats per minute, respiratory rate of 6-10 per minute. Living physical labor makes the muscle work with a smaller increase in oxygen consumption and with greater efficiency. With extremely hard work in trenirovka the body is much larger mobilization of the circulatory, respiration, energy metabolism compared to untrained.
Changes in the human body under the influence of physical activity:
In the body of every person under the influence of heavy physical labor in the cells of organs and tissues, which decreases physical activity, activates the synthesis of nucleic acids and proteins. This activation leads to selective growth of cellular structures responsible for adaptation to physical load. As a result, firstly, increase the functionality of the system, and secondly, the time shifts are transferred to the permanent strong bond.
Changes in the human body due to intense muscle activity in all cases represent the reaction of the whole organism, aiming at achieving two objectives: ensure muscle activity and maintain a constant internal environment (homeostasis). These processes are run and controlled by the Central control mechanism, having two links: neurogenic and humoral.
Consider the first link that controls the process of training the body on a physiological level, neurogenic link.
The formation of motor responses and mobilization of vegetative functions in response to starting the muscle work are provided in human Central nervous system (CNS) based on the reflex principle of coordination functions. This evolutionary principle is provided by the structure of the Central nervous system, namely, that of the reflex arc are connected a large number of inserted cells, and the number of touch several times exceeds the number of motor neurons. The predominance gusset and sensory neurons — morphological holistic and coordinated response of human organism to physical activity, other external environment.
In the implementation of various movements in humans can take part of the structure of the medulla oblongata, the quadrigemina, podvorovoy region, cerebellum, other lesions of the brain, including higher education center — motor area of the cerebral cortex. In response to muscular stress (thanks to numerous connections in the Central nervous system) is the mobilization of the functional system responsible for motor response in the body.
The whole process starts with a signal, most often conditioned reflex, encourage muscle activity. Signal (afferent impulses from receptors) to the brain cortex in the control center. “The control system activates the appropriate muscles, affects the centres of respiration, circulation, and other supporting systems. Accordingly, physical exercise increases pulmonary ventilation, increased cardiac output, redistribution of regional blood flow, inhibited the function of the digestive system.
Improving governance and peripheral motor apparatus of the system is achieved in the process of repeating signal and the response of the muscle of the operation (i.e. during exercise). In this process, “management system” is fixed in the form of a dynamic stereotype and the human body acquires the skill of physical activity.
The expansion of the number of conditional reflexes in the process of training the person creates the conditions for better implementation of the phenomenon of extrapolation in motor acts. An example of the existence of extrapolation could be the movement of a hockey player in a complex, continuously changing environment of the game, the behavior of the driver-professional unknown on a difficult track.
Simultaneously with the receipt of a signal on the physical load is neurogenic activation of the hypothalamic-pituitary and sympathoadrenal systems, which is accompanied by intense release into the bloodstream of the relevant hormones and neurotransmitters. This is the second link mechanism of regulation of muscle activity, humoral. The main results of the humoral response in response to physical activity include the mobilization of energy resources; redistribution of them in the human body to organs and tissues subjected to load; potentiation of operation of the propulsion system and ensuring its mechanisms; the formation is the structural basis of long-term adaptation to physical load.
By muscle load in proportion to its size there is an increase in the secretion of glucagon, increasing its concentration in the blood. At the same time decreases the concentration of insulin. Naturally increases the yield in the blood of growth hormone (GH — growth hormone) that is caused by the increased secretion in the hypothalamus of somatoliberin. The secretion of this hormone gradually increases for a long time and remains elevated. The untrained body’s secretion of the hormone can not block the increased capture of his tissues, so the level of this hormone untrained persons at heavy physical workload significantly reduced.
The physiological implications of the above and other hormonal shifts is determined by their participation in the energy supply of muscular work and the mobilization of energy resources. Such shifts are important activating in nature and confirm the following:
1. Activation of the motor centers and hormonal shifts induced by exercise, care for the Central nervous system. Small and moderate exercise will activate the processes of higher nervous activity, improve mental performance. An intensive period of activity, especially with debilitating consequence, caused the opposite effect, dramatically reduce mental performance.
2. Unsuitable to physical exercise the human body can not cope with intense and long-lasting impacts. For high productivity, where is a significant physical component, it is necessary to purchase as specific to this specialty skills, and nonspecific physical fitness.
3. Physical warm-up (gymnastics, a variety of metered load, rational exercises to relieve fatigue sitting postures, etc. types of workout person) is an important factor in improving health, especially during inactivity and hypokinesia. monotonous types of labour .
4. Both in work and in sport achievements can be obtained only by using built based on scientific medical evidence of a rational system of exercises and workouts.
5. Hard physical labor for an untrained body were long without exercise, just as a sudden withdrawal of intensive physical work (especially in athletes-marathoners, skiers, weightlifters), can cause rough shifts in the regulation of transitioning to temporary health problems or persistent disease.