Get up in the morning. Blood sugar is low and blood is thick. Running on an empty stomach is actually harmful to health. Because when running on an empty stomach, people's blood sugar level will drop rapidly. When the blood sugar level is low, it is easy to induce hypoglycemia, fainting and arrhythmia. So eat a small amount of carbohydrates such as biscuits before jogging in the morning.
Because the blood sugar level in the human body is low on an empty stomach, and blood sugar is the only source of brain energy, running on an empty stomach will further reduce the blood sugar content and make the brain lack the necessary energy source, which will easily lead to hypoglycemia such as dizziness, limb weakness and even syncope. Although free fatty acids in blood can be the energy source of muscles such as myocardium, the utilization efficiency of fatty acids in myocardium is not very high. Too many fatty acids may cause various arrhythmias and even sudden death. Although there are not many such examples, facts show that there are several famous middle-aged and elderly joggers in history who exercise on an empty stomach and cause sudden death.
In addition, due to insufficient sugar content, some fats will not be completely oxidized, and eventually some ketone bodies will be generated, while too many ketone bodies in the body will easily cause human acidosis. In addition, fasting exercise is easy to make people feel hungry, and may also cause abdominal pain, which affects people's normal digestive function. For the above reasons, I suggest you don't exercise on an empty stomach. If you are used to exercise on an empty stomach, you can add a small amount of carbohydrates, such as juice and honey, before exercise. This is especially true for middle-aged and elderly people, because there are many people with hypertension and diabetes in the middle-aged and elderly party. Due to age and physical factors, their ability to use fatty acids is lower than that of young people, so they should try to avoid fasting exercise.