Improve cardiovascular system
Swimming plays an important role in improving cardiovascular system. The stimulation of cold water can promote blood circulation through heat regulation and metabolism; In addition, the pressure and resistance of water also play a special role in the heart and blood circulation. When swimming on the water, the water pressure on the body has reached 0.02-0.05 kg per square centimeter. When diving, with the increase of depth and the change of physical conditions, the pressure will increase, and the speed of swimming will also increase the pressure load. The muscle tissue of atrium and ventricle can be strengthened, the volume of heart cavity can be gradually increased, and the beating times of heart can be reduced. This can preserve the activity of the heart, but it can improve the whole blood circulation system. At rest, diastolic blood pressure increases and systolic blood pressure decreases, so the blood pressure value becomes more favorable. The elasticity of blood vessels has also improved. According to the statistics of relevant experts, the average person's heart beats about 66-72 times per minute in a quiet state, and the stroke output is about 60-80 ml, while those who take part in swimming exercises for a long time only need to contract about 50 times under the same circumstances, but the stroke output reaches 90- 120 ml.
When people exercise in water, all organs participate in it, which consumes a lot of energy, accelerates blood circulation and provides more nutrition for sports organs. The acceleration of blood speed will increase the load on the heart, make the heart beat faster and contract strongly. People who swim regularly have excellent heart function. The average person's heart rate is 70-80 beats per minute, and the stroke output is 60-80 ml. Frequent swimmers' heart rate can reach 50-55 beats/min, many excellent swimmers can reach 38-46 beats/min, and the stroke output is as high as 90- 120ml. When swimming, the role of water makes it easy for limb blood to flow back to the heart and accelerate the heart rate. Long-term swimming will obviously increase the activity of the heart, contract strongly, increase the thickness and elasticity of the blood vessel wall, and increase the stroke output. Therefore, swimming can exercise a strong heart.
increase lung capacity
Breathing mainly depends on the lungs, and the strength of lung function is determined by the strength of respiratory muscle function. Exercise is one of the effective means to improve and increase vital capacity. According to the measurement, when swimming, people's chest is under the pressure of 12- 15 kg. Cold water stimulates muscle contraction, making it difficult to breathe, forcing people to breathe hard, increasing the depth of breathing, and making the amount of oxygen inhaled meet the needs of the body. The average person's vital capacity is about 3200ml, and the breathing difference (the difference between the expansion and contraction of the chest circumference at the maximum inhalation and exhalation) is only 4-8 cm. The maximum oxygen uptake during strenuous exercise is 2.5-3 liters/minute, which is 10 times higher than that at rest. The swimmer's vital capacity can be as high as 4000-7000ml, the breathing difference can reach 12- 15cm, and the maximum oxygen uptake during strenuous exercise is 4.5-7.5 liters/min, which is 20 times higher than that at rest. Swimming makes people develop respiratory muscles, increase chest circumference, increase vital capacity and open more alveoli when inhaling, which is very beneficial to health.
Strengthen skin blood circulation
During Phelps' swimming, due to the stimulation of water temperature, his body wanted to keep enough temperature. Skin blood vessels play an important regulatory role. Stimulation of cold water can make skin blood vessels contract and prevent heat from spreading outward. At the same time, the body will intensify the generation of heat, dilate the blood vessels of the skin and improve the blood supply of the blood vessels of the skin, so that long-term exercise can strengthen the blood circulation of the skin.
In addition, water is a very soft liquid. Because of the action of water waves, it constantly rubs the human epidermis and makes the skin relax and rest better, so people who often take part in swimming exercises have smooth, fair and soft skin.
When people swim, the water washes away the skin, sweat glands and fat glands, which plays a good massage role, promotes blood circulation and makes the skin smooth and elastic. In addition, when exercising in water, it greatly reduces the irritation of salt in sweat to the skin.
Enhance immunity
The water temperature in the swimming pool is often 26 to 28 degrees, so soaking in water dissipates heat quickly and consumes a lot of energy. In order to supplement the heat emitted by the body as soon as possible and meet the needs of cold and heat balance, the nervous system reacts quickly, accelerating the metabolism of the human body, enhancing the adaptability of the human body to the outside world and resisting the cold. People who often take part in winter swimming are not easy to catch a cold because of the improvement of body temperature regulation function, and can also improve the endocrine function of human body and increase the function of pituitary gland, thus improving the resistance and immunity to diseases.
lose weight
When swimming breaststroke, the body is directly immersed in the water, which not only has great resistance, but also has very good thermal conductivity and fast heat dissipation, so it consumes a lot of heat. Like a boiled egg, the cooling rate in air is far less than that in cold water. Experiments show that the heat consumed by a person running in a standard swimming pool for 20 minutes is equivalent to running at the same speed 1 hour on land, and the heat consumed by staying in water with 100 minutes is as high as 100 kcal, which is equivalent to being in air with the same temperature. In addition, swimming diet can avoid sports injuries of lower limbs and waist. When you exercise on land to lose weight, your body (especially lower limbs and waist) will bear great gravity load because of the heavier weight of obese people, which will reduce your exercise ability and make you tired easily, thus greatly reducing your interest in losing weight and damaging the joints and bones of lower limbs. When swimming in water, a considerable part of obese people's weight is borne by the buoyancy of water, which makes their lower limbs and waist much easier and greatly reduces the risk of joint and bone injury. It can be seen that water sports make many people who want to lose weight get twice the result with half the effort. Therefore, swimming is one of the most effective aerobic exercises to keep healthy.
Bodybuilding figure
When children swimmers swim, they usually use the buoyancy of water to lie prone or supine in the water, so that the whole body can be relaxed and stretched, so that the body can develop in an all-round, symmetrical and coordinated way and the muscle lines can be smooth. Exercise in water reduces the impact of the ground on bones, reduces the probability of bone aging, and the joints are not easy to deform. The resistance of water can increase people's exercise intensity, but this kind of intensity is very soft, which is different from the equipment training on land. The training intensity is easily controlled within the aerobic range, so that stiff muscle blocks will not grow and the whole body lines will be smooth and beautiful.