Weather thermal movement

The summer solar term has passed, marking the beginning of the dog days. The hottest day of the year has arrived. In the next few days, runners will run in a hot environment. Are you ready? Some runners are afraid of heatstroke and dehydration caused by exercise. At this time, some runners with weak physique will simply give up running on the grounds of hot weather, and some articles exaggerate the risks of summer sports and aggravate the runners' fear of sports in hot environment. So, is running in summer really easy to get heatstroke? How does your body react when you run in a hot environment? What are the precautions for running in high temperature environment?

1. What are the reactions to running in dog days?

1, cardiac function and muscle contraction were inhibited to some extent.

Exercise in a hot environment, in order to dissipate heat, a large number of blood vessels on the body surface dilate and the blood flow of the skin increases, because the total flow of the human body is certain. Therefore, the blood flow through the muscle is relatively reduced, which may lead to the decrease of muscle contraction ability. In a hot environment, moderate and high-intensity running will also lead to the accumulation of lactic acid in advance and produce more lactic acid.

In addition, under the same intensity, when exercising in a high-heat environment, the heart rate increases obviously, and the myocardial contractility decreases, which is related to factors such as the increase of body surface blood flow, the decrease of blood volume, the increase of sweating, and the acceleration of heart rate. Therefore, you will feel more tired in summer exercise and fatigue will come earlier.

Step 2 sweat a lot

Exercise at high temperature, sweating has become the main way to dissipate heat. You will sweat a few seconds after exercise. Although the loss of water is more than the loss of salt, the electrolyte will also be lost due to the obvious increase of sweating, which may lead to dehydration and electrolyte disorder in the body. Sweat evaporation can reach 3 liters/hour or 12 liters/day during exercise in summer.

3. Impaired endurance

No matter whether there are trainers or not, the endurance will decrease when exercising in high temperature environment, but the endurance performance of those with higher aerobic capacity is better than that of those without trainers. Some trainers are tired at 39℃, and 38℃ without training.

Second, don't exaggerate the danger of summer sports.

The human body is a warm-blooded animal, that is to say, the temperature of the human body basically remains dynamic and stable, and the temperature change of the human body in different environments does not exceed 65438 0 degrees. Even in hot or cold environment, the body temperature can be kept between 36.65,438+0-37.8 degrees through the temperature control device. In summer exercise, in order to prevent excessive temperature rise, the human body will increase heat dissipation through a large number of blood vessels and sweating on the body surface.

It is found that after two weeks of continuous exercise in a high temperature environment, the human body will gradually adapt to the high temperature environment, which is called thermal acclimatization. Heat acclimatization is mainly manifested in the improvement of body temperature regulation, water and salt metabolism and cardiovascular function. As a result, heat generation is reduced and heat dissipation is increased. What are the manifestations of hot acclimatization?

1, sweating threshold decreases, sweating rate increases, and perspiration ability increases.

The maximum sweating rate of trainers in summer is increased from 1.5 liter/hour to 2.5-3 liter/hour, which is greatly beneficial to heat dissipation. Besides.

People who don't train and don't adapt to the hot environment begin to sweat when their body temperature reaches 37.7℃

Those who are trained and unaccustomed to hot environment begin to sweat when their body temperature reaches 37.5℃

People who are trained to adapt to the hot environment begin to sweat when their body temperature reaches 37.2℃.

In other words, people who insist on training in a hot environment will improve their sweating sensitivity and sweating ability, which is of course beneficial to heat dissipation.

2. Salt loss with sweat decreases.

Heat acclimation increases the reabsorption of salt by kidneys and sweat glands, that is, the salt in sweat decreases and remains in the body, so electrolyte disorder is not easy to occur.

It is found that the concentration of electrolytes such as sodium and potassium in sweat of trained and untrained athletes is obviously different.

3. Improvement of cardiac function

After heat adaptation, the heart rate will not jump so fast in the hot environment, the cardiac contraction function will also be enhanced, and the skin heat dissipation will increase, but the skin blood flow will decrease relatively, and the muscle blood flow will increase, which will help improve the muscle working ability.

Third, the benefits of running in dog days.

Running in a hot environment, the various functions of the body gradually adapt to the hot environment, greatly reducing the risk of heatstroke and dehydration. In fact, running in summer has many benefits. Why do you say that?

1. Get ready for the coming autumn.

In the eyes of athletes and coaches, there are few competitions in summer and winter, which is just a good training season, called summer training and winter training. A solid summer training can completely change the physical quality of the whole person. After September, the marathon in the second half of the year will be held intensively in major cities. Wait until the weather gets cold before running? At this time, the game is approaching, and sharpening the knife will not miss the woodcutter. Forward-looking and serious runners will make full use of summer for necessary training and competition preparation.

2. Getting rid of air-conditioning diseases and sweating through running are of great benefit to health.

Humans invented air conditioning, so they don't have to endure the heat in summer, but the following problem is that their adaptability to the thermal environment is reduced. Everyone may feel this way. When I was a child, there was no air conditioning at home, and the fan was still very comfortable in summer. Without air conditioning now, everyone can't live.

Although air conditioning has created a seemingly comfortable environment for us, if we stay in the air conditioning environment from morning till night, some people will feel various discomforts because of the relatively closed space, poor air circulation and large temperature difference between indoor and outdoor, which are collectively called "air conditioning disease" or "air conditioning disease".

At this time, you need a run to make yourself sweat well and ensure that the normal physiological function of sweating in summer can play a role. Since ancient times, Chinese medicine has also said "sweating for health and treatment", which means that the human body should conform to the laws of nature and keep sweating normally in summer. So here we are not against the use of air conditioning in summer, but suggest that you don't always covet coolness. It is definitely good for your health to make yourself sweat through proper running.

3. hone your will and be the strongest runner.

Running is a long-term and high-intensity exercise, which itself is a tempering of the quality of will. Running in high temperature environment in summer is more difficult. Those who can keep running in dog days are the real runners! Moreover, after running in summer, you will magically feel that the surrounding environment seems to be less hot.

Fourth, the precautions for running in summer

Although the human body can adapt to the hot environment, running in summer is definitely good for the body, but if you don't pay attention to the method, the risk of dehydration and heatstroke still exists, so you should pay attention to the following points when running in the hot environment:

1, more water. It is recommended to drink 500-800 ml of water before running 1-2 hours in dog days. The more water you have before running, the lower the risk of dehydration. Water is pumped through running pockets or running backpacks, and a small amount of water is replenished many times during running. Drink 80- 100 ml water every time, and add white water for running within 1 hour. If you run more than 1 hour, you need to supplement sports drinks containing electrolytes. At the same time, the amount of hydration after exercise must be greater than the amount of perspiration (equivalent to 150%-200% perspiration), which can be weighed before and after exercise.

2. Breathable, light and quick-drying clothes. Try to choose breathable and quick-drying clothes for running in hot environment, which will help to dissipate heat and lower body temperature.

3. Reduce the amount of exercise appropriately. In a hot environment, the amount of exercise is kept at 70%-75% of the daily amount of exercise. For example, if you run 10 km, you only need to run 7-7.5 km in a hot environment.

4. Avoid cold drinks after exercise. Some runners like to drink a cold drink immediately after running. Although they are happy, their body temperature is very high at this time. Eating cold drinks will cause excessive irritation to the intestines, which may easily lead to indigestion, diarrhea, abdominal pain and other symptoms. Just drink normal temperature white water or sports drinks after running in summer.

5, running in summer is uncomfortable, first think of possible heatstroke. Running in a hot environment consumes a lot of energy, and all the functions of the human body are in a bad environment. If you have symptoms such as headache, dizziness, vomiting and muscle spasm, you should first think of heatstroke. At this time, stop exercising immediately, find a cool and ventilated place, replenish water quickly, keep calm, and call 120 or ask for help if necessary.

6. Try to choose a cooler morning, noon and evening for running, and avoid running at noon or in the hottest afternoon.

Summer is the most active season for human metabolism. As long as we pay attention to exercise methods and combine work and rest, we can achieve better running results, improve our physical fitness and run happily all summer. In dog days, melodramatic people don't run, but those who really run have so many excuses!