2. If the blood sugar before meals is obviously low, generally doing aerobic exercise during fitness will consume a lot of ATP and calories. At this time, gluconeogenesis and glycolytic pathway will increase, leading to hypoglycemia. For example, after a lot of exercise before meals, hypoglycemia will occur, and even lead to hypoglycemia coma. You have to wait 30-40 minutes after dinner. At this point, the food has been basically digested in the gastrointestinal tract. At this time, the blood will refill the skeletal muscle, so the exercise time after meals is the most appropriate.