Hello, the best aerobic depends on the running time, usually within 45~90 minutes. As long as you are running, you can run as slowly as you want, no matter how many meters you run. In fact, the best time is afternoon, the air quality is the best, and the oxygen ion content is very high. But personally, as long as it is the right exercise, it doesn't matter at any time, and it can also achieve the purpose of exercise and achieve the desired effect.