When you exercise on an empty stomach, your body will choose to protect your protein, so it will burn fat first, because your body's insulin and glycogen levels are relatively low, which is a wise choice made by your body.
So on an empty stomach, your body will burn more fat and carbohydrates, which is what you want to throw away, and your body will give priority.
Similarly, when we are on an empty stomach, we can do things efficiently. When we work in the morning or in other ways, we find that working on an empty stomach is always efficient, so running on an empty stomach is the same.
In addition to running, fasting training should also do some aerobic training. In the gym or at home, if conditions permit, choose aerobic training on an empty stomach.
For example, walking on slopes and simple cycling are all better choices for fasting exercise.
High-intensity aerobic exercise and interval training are also possible. But this should be used with caution, because they will cause more muscle damage and make your muscles consume more glycogen.
At the end of the day, we should make sure that our calorie deficit is the most important thing.