If you get up before dawn in the morning and don't eat or drink, then running is definitely harmful to your health. Because all the functions of the body are at a low point at this time, the adjustment function is unstable, and the physiological characteristics determine that it is not suitable for exercise. The reasons are roughly as follows:
1, the physiological function is relatively low: when I just got up in the morning, the cerebral cortex was not fully excited, the physiological function was still in a certain state of inhibition, and the functions of various organs of the human body were relatively low. Some data show that muscle speed, strength and endurance are in the worst state from 3 am to 5 am. The best exercise time should be when the physiological function of exercise is the best, when the physical strength, agility and adaptability reach the peak, and when the heart rate and blood pressure rise most steadily, physical exercise is the most beneficial to health. When the motor function is the worst, it is easy to get tired and the probability of sports injury will increase.
2. Hypothermia: Scientific research has found that the change of body temperature will greatly affect the quality and effect of exercise, that is, the higher the body temperature during exercise, the better the effect.
3, the blood is sticky, prone to thrombosis: in the long night, there is no water intake, but water is continuously lost through the skin, mucosa, urine, etc. , make the blood thick in the morning, slow down the flow rate, and increase the chance of thrombosis; On the other hand, the oxygen demand of muscles increases during exercise, and viscous blood is not conducive to muscle blood supply.
4. Heavy heart load, unstable regulatory function, and increased risk of sudden death: Sports medicine experts have found that the heart rate and blood pressure rise faster in the morning than in the afternoon, and the heart burden is heavier, which is easy to cause relative myocardial ischemia and increase the risk of sudden death during exercise. A survey by researchers at Harvard Medical School in the United States found that the peak of heart attack is from 6 am to 9 am every day. Therefore, patients with heart disease should avoid exercise during this period.
From the external environment, running too early is not good for health. This is because plants can't carry out photosynthesis before the sun comes out. After a night of breathing, the concentration of carbon dioxide in the air is high, which is not suitable for running and consumes a lot of oxygen. On the other hand, if the morning fog persists, harmful chemicals such as acid, alkali and benzene dissolved in the fog, suspended dust and pathogenic microorganisms attached to it will all cause damage to the respiratory tract, and infection will occur when the resistance is low.