Fitness running exercise is generally arranged in the morning is the best, followed by about 9:00 am and 5:00 pm. The air is fresher in the morning, which is good for the respiratory system. In addition, people recover after sleep, but physiologically there is still a certain state of inhibition, the morning exercise is conducive to nerve excitement, invigoration, and promote metabolism. However, it is not recommended to run on an empty stomach, especially for large exercise on an empty stomach, such as fitness long-distance running, do not run when the distance is very long. Running on an empty stomach will make some people have symptoms of hypoglycemia, and for people who lose weight, running on an empty stomach can burn fat, but it will increase the chances of weight rebound, and it will also cause harm to the body. So before you want to run in the morning, you can drink a small cup of sugar water or eat less snacks and other foods.