In the process of physical education class and exercise, people often ignore the coordination and coordination of exercise and breathing. Many physical education teachers have not realized or noticed the importance of how to use breathing well and how to use breathing reasonably while teaching students sports techniques and methods. As we all know, incorrect breathing methods will directly affect the exertion of exercise level and the decline of physical fitness. Based on years of teaching experience, the author intends to discuss the following four aspects with you in theory and practice. First, the form, phase and rhythm of breathing should adapt to the changes of technical movements, and the form, phase and rhythm of breathing must be freely adjusted with technical movements, which provides a guarantee for improving the quality of movements and cooperating with the completion of difficult techniques. (1) The breathing forms combined with technical movements are mainly divided into two categories: the breathing form mainly based on chest movements is called thoracic breathing, and the breathing form mainly based on diaphragm movements is called abdominal breathing. What kind of breathing mode should be adopted should be changed flexibly according to the principle that it is beneficial to breathing form and does not hinder the application of technical movements. Usually, some technical movements need the fixation of the chest and shoulder straps to ensure the shape, so the breathing form is changed to abdominal breathing. For example, handstand, shoulder handstand, head handstand, cross-hanging rings and "bridge" movements in gymnastics, which need to be fixed on the chest and shoulder straps, will eliminate the factors affecting the instability of the body's center of gravity if abdominal breathing is adopted; Other technical movements need abdominal fixation, which should be converted into chest breathing, such as static movements of bending the body when fixed above or below, and static movements of "lifting from both ends". The use of chest breathing helps to maintain and complete abdominal movements. (2) Coordination of breathing phase and technical movements Usually, non-periodic movements should pay special attention to breathing phase. When to inhale and exhale depends on the anatomical characteristics of human joint movement and the structural characteristics of technical movements. Generally speaking, it is more beneficial to use inhalation when completing the flexion, abduction, external rotation, chest expansion, shoulder lifting, body stretching or anti-bow movements of both arms; Exhale is more convenient when doing the opposite actions as mentioned above, such as arm flexion, adduction, pronation, chest contraction, shoulder collapse, body bending or group body movement. However, there are exceptions (such as barbell squatting, standing with weight, it is better to exhale), and then consider the cooperation of inhalation and exhalation on the basis of completing technical movements. The example shows that in the "bench press barbell" exercise, the barbell should be lowered by inhalation and lifted by exhalation. "Sit-ups" exercise, inhaling during the supine process (exhibition) and exhaling during the supine process (flexion); "Push-ups" exercises, inhaling during the prone process (arms abduction and chest expansion) and exhaling during the supporting process (arms adduction and chest adduction). (3) Coordination between breathing rhythm and technical movements In normal times, special attention should be paid to breathing rhythm during periodic exercise. Rhythmic breathing will make exercise easier and more coordinated, which is more conducive to creating good sports results. If running periodically, long-distance running should take 2 ~ 4 steps of inhaling and 2 ~ 4 steps of exhaling at a time. In sprint, the method of "holding your breath" and intermittent shortness of breath is often adopted, that is, after "holding your breath" for every 2 to 12 single step (or more), take a quick deep breath within 1 second. The breathing rhythm of periodic swimming, breaststroke is a combination of one stroke, one kick and one head out of the water to complete one breath, and crawl is a combination of three strokes, three kicks and three to six times to complete one breath (lateral ventilation). Second, save breathing frequency and focus on increasing breathing depth. The purpose of breathing during deep breathing exercise is to ensure that more oxygen-containing fresh air is expected in the alveolar cavity when inhaling, and more metabolic gas containing carbon dioxide is expected to be exhaled when exhaling. Exercise anatomy and exercise physiology tell us that the respiratory system consists of two parts. One part includes the respiratory airway (about 1.50ml) that can't breathe gas at all levels, which is called anatomical dead space, and the other part is an alveolar cavity formed by 600 million to 700 million alveoli that can exchange gas. Because of the anatomical void, the fresh air inhaled every time can't reach the alveoli for gas exchange. Therefore, to calculate the truly effective and exchanged gas, it should be based on the alveolar ventilation entering the alveolar cavity, or subtract the inhaled fresh air from the anatomically ineffective cavity, which is the truly effective gas to be exchanged. Deep breathing can inhale more effective fresh air in alveolar cavity, while shallow breathing can only reduce alveolar ventilation and gas exchange. Then, when exercising, do you emphasize deep breathing, mainly deep breathing or body exhalation? When the effective alveolar gas inhaled remains unchanged, the air freshness rate in alveolar cavity depends on the original gas in alveolar cavity at the end of expiration or before inhalation, which is called functional residual volume. The less functional residual gas, the more fresh air inhaled into alveolar cavity, which improves the fresh rate of gas in alveolar cavity and provides sufficient oxygen supply. An effective way to reduce the functional residual gas in alveolar cavity during exercise is to do deep exhalation as much as possible (sometimes called deep exhalation). Therefore, in the process of exercise (especially in the case of dyspnea and severe hypoxia), rhythmic deep exhalation is more helpful to provide fresh gas content in alveolar cavity than deep inhalation, and enhance the anti-hypoxia ability of human body during exercise. For example, when running or swimming, people often feel particularly uncomfortable for a while, such as chest tightness, wheezing, dyspnea, dyskinesia, depression and so on. The direct cause of this result is that the respiratory and circulatory functions of the body do not adapt to the strenuous exercise of the body, resulting in hypoxia of the body. In the case of hypoxia, a large number of acidic substances produced by metabolism accumulate and block up, forcing the human body's exercise ability to decline, which will definitely lead to fatigue. The above phenomenon is also called "pole" phenomenon. The effective breathing method to overcome or alleviate this "pole" phenomenon is: in order to inhale more fresh air and improve oxygen intake, we should pay more attention to deep exhalation (deep exhalation) on the basis of keeping deep breathing rhythmically. The correct breathing in swimming should be to take a deep breath in the water, spit it out, and then raise your head and breathe in. In addition, deep breathing will reduce the frequency of breathing, thus avoiding excessive consumption of energy and oxygen due to muscle contraction caused by deep breathing and making breathing more economical and effective. Three, the correct use of breath holding or deep inhalation or shallow inhalation, close the glottis, try to exhale, this is called breath holding. It is usually necessary to hold your breath when completing the maximum static exercise, such as carrying weights, lifting weights, wrestling, tug-of-war, "arm wrestling" and so on. Holding your breath has a good effect on exercise: holding your breath can reflect the increase of muscle tension and create the most effective contraction support conditions for related sports links. However, people only see the beneficial side of holding their breath, and they don't know that holding their breath will have a negative effect on the human body. The adverse effects of holding your breath mainly include: First, holding your breath increases the internal pressure in the chest, which prevents venous blood from returning to the heart, and then the heart is not fully filled, the output drops sharply, and the blood pressure drops sharply, resulting in insufficient blood supply to the myocardium, brain cells and retina, and symptoms such as dizziness, nausea, tinnitus and black eyes appear, which affects and interferes with the normal exercise; Second, at the end of breath-holding, there will be reflective deep breathing, which will cause the pressure in pleural cavity to drop sharply. The blood originally trapped in the vein will quickly return to the heart, impact the myocardium, make it overstretched, and the blood pressure will also rise sharply, which will have serious adverse consequences for children's hearts, and it is easy to overstretch and relax the myocardium. For the elderly, it is easy to damage the blood vessels in the heart, brain and eye due to poor blood vessel elasticity and brittleness. From this perspective, holding your breath has advantages and disadvantages for exercise. Sometimes you need to struggle and hold your breath to win the final victory. Then the necessary and correct and reasonable way to hold your breath should be not to inhale too deeply before holding your breath; In order to gradually reduce the internal pressure in the pleural cavity, the exhaled air should gradually squeeze out of the glottis slightly and moderately, that is, the larynx exhales with a "hi" sound; Hold your breath in the critical moment of winning the game, not every movement and every process needs to hold your breath. Fourth, the role of simultaneous breathing of the nose and mouth During activities, breathing with the nose and mouth at the same time has three advantages over breathing only through the nose or mouth: First, it can reduce the ventilation resistance of the respiratory tract and increase the ventilation volume; Second, the muscles that do not need breathing exercise increase extra consumption to overcome greater resistance and delay the appearance of fatigue; The third is to expose the mouth full of blood vessels, which increases the heat dissipation. In addition, when exercising in winter, the mouth opening should not be too big, and the inhaled fresh air should be warmed through the mouth as much as possible before entering the trachea and lungs to prevent diseases such as colds and tracheitis. To sum up, it is very important to use breathing reasonably during exercise. Physical education teachers should teach students to master breathing skills suitable for the characteristics of the sport, just like teaching technical movements. Only by reasonable breathing can we keep the internal environment of human body basically constant, fully choose the functional ability of human body and improve the effect and level of exercise.