EFFECTS ON BONES
The bones constitute the scaffolding of our body, they fulfill the task of protection (the skull protects the brain, the spine protects the marrow) and contribute, as passive organs to the movement, to the displacement of the body and its limbs. The movement produces the following transformations on the bones:
1 better nutrition: the increased circulation of blood, caused by physical exercise, nourishes the bone tissue and supplies it with calcium.
2 development in length: the movement favors the production of new bone cells, which determines the growth in length of the bone itself.
3 development in width and thickness: the tractions on the bones, exercised by the muscles during movement, favor the development of the same in thickness and width. It follows an increase in resistance.
RESPIRATORY EFFECTS
The task of the respiratory system is to supply the body with oxygen and to eliminate carbon dioxide. The movement produces the following transformations on breathing:
1 reduction of recovery time: the trained subject takes less time to return to normal breathing after the effort.
2 minor increase in respiration rate: the trained subject, with the same work, has a lower basal respiratory rate than the sedentary (12-16 acts per minute).
3 increase in vital capacity: the vital capacity is the amount of air, measured in liters with the spirometer, which is able to emit with a forced exhalation, after having done a maximum inhalation.
4 increase of the apnoea time: the apnoea, or voluntary suspension of the breath, increases in duration in the trained subject.
5 strengthening of the respiratory mechanics: the respiratory muscles, and in particular the diaphragm, with the exercise increase their power and the efficiency of their contractions.
EFFECTS ON THE HEART AND CIRCULATION
The circulatory system consists of the heart (pump), the great circulation (arteries and veins that carry blood to the various tissues, the organs of the body and bring it back to the heart), the small circulation (which brings blood to the lungs to oxygenate them and brings it back to the heart).Physical activity produces evident effects on the cardio-circulatory system, among these the most expressive are:
1 the shape of the heart changes: the heart of an athlete becomes almost spherical.
2 the heart becomes thicker: the internal cavities (atriums and ventricles) increase in volume and the muscular walls thicken.
3 the systolic range increases: the amount of blood expelled at each contraction (systole) of the heart is greater because the internal volumes and muscle strength have increased.
4 cardiac output increases: the amount of blood put into circulation in one minute.
5 heart rate increases: the number of pulses per minute increases during work. Remembering that with the same work, the trained subject will have a lower number of pulsations thanks to the capacity of his heart to pump a greater quantity of blood.
6 reduction of the pulsations at rest: this is one of the most easily controllable effects, but it is achieved only thanks to constant and prolonged training.
7 reduction of recovery time after exertion: the trained subject returns more quickly to the cardiac rhythm of rest than the sedentary subject.
8 increase in the capillaries of the heart: the heart is better sprayed and better nourished.
9 increase of the capillaries in the muscles: the opening of new channels of blood circulation is important to improve the nutrition of the muscles and to eliminate more quickly the slags produced by the muscular contraction.
10 blood rerouting: when engaged in intense physical work the blood is channeled to the muscles engaged and is subtracted from other sectors. They are mainly the intestine, the stomach, the liver and the spleen to give blood for muscle work. For this reason, those who are poorly trained, accuse pain in the right or left side.
11 facilitating the return of blood to the heart: during movement, the muscles, with their contraction, “massage” and “squeeze” the veins that, thanks to the dovetail valves, convey blood towards the heart.
EFFECTS ON DIGESTIVE FUNCTION
Physical exercise accelerates all digestion, from mechanical to chemical and secretive. Exercise strengthens and speeds up stomach and bowel movements.
EFFECTS ON THE NERVOUS SYSTEM
The Central Nervous System (CNS) consists of:
- brain;
- cerebellum (balance);
- brain stem;
- spinal cord.
The Peripheral Nervous System (PNS) consists of:
- 12 pairs of cranial nerves;
- 31 pairs of spinal nerves;
- sympathetic system (regulates heart beats, respiratory acts, blood pressure);
- parasympathetic system (regulates the digestive system and balances the reactions caused by the sympathetic system).
Movement is the most visible act produced by the nervous system: it is the motor response to nervous excitement.
In order for the movement to take place, three phases are necessary:
1) information;
2) processing;
3) knowledge.
After receiving the information (kicking the ball) an ideomotor scheme is created using the memory of similar movements already performed previously. Once the schema has been prepared, the brain produces the nerve stimuli suitable for making the right muscles contract with the right force and in the correct sequence. In the voluntary movement, especially if never done before, the times related to the three phases will be long. When the movement has already been repeated several times, it becomes automatic because the motor scheme is already known and ready; the execution of the gesture becomes faster and more precise; motion control has been automated. Therefore the motor exercise trains and educates the sensory organs, improves and sharpens the visual, auditory, tactile, proprioceptive (ability to analyze the position of our body with eyes closed) and balance.
PSYCHIC AND SOCIAL EFFECTS
Motor activity develops:
a) cognitive ability;
b) the imaginative capacity;
c) practical capacity.
The motor activity improves:
a) attention;
b) the memory.
When you are preparing to do a sports exercise, you behave like when you are preparing to understand a concept, to grasp a truth, to solve a math problem. First the data are brought into focus, that is to say, what is available and the objectives to be achieved; then the difficulties to be overcome are analyzed; then it is reflected and moves on to action; and finally, the results are checked and their accuracy checked. It is easy to understand how sport stimulates our emotional states and our passions (joy, enthusiasm, satisfaction, pride, etc.).Sports activity helps those who have problems of shyness and insecurity because they are used to courage and trust in themselves.
SOURCES FOR ENERGY PRODUCTION
Muscle fibers
It is known that the quality of the contraction of a muscle depends, essentially, on the percentage of the type of fibers that compose it. The endowment or the percentage distribution of the different muscle fibers is genetically determined
(Weineck 2001).
There are two main types