12 years old, if you want to exercise, you should stick to three groups every day, each group 12, and rest for about 30 seconds a week, and the number will increase to 15. If possible, it is best to add 2 to 5 per week. If your physical strength is obviously exhausted, don't be eager for quick success. Each group is limited to 50 (too much is bad for the waist). With aerobic exercise such as jogging, the effect will be better. Just spend 20 minutes jogging every day, either in the morning or at night. If you don't have enough time, you can choose skipping rope or walking fast or other quick and convenient methods.

If it exceeds 40KG, it will be a little fat. It may be more difficult to do so. At the beginning, there were about 7 in each group, and the rest were the same, increasing by 2 to 5 per week.

The above two points should be adhered to every day, and the number of groups should not be less and the number should not be less. It is best to do it at the same time every day. If you can guarantee these, the effect will be more obvious if you persist for a month or two at your age.

All of the above are personal experiences. If you want to meet the high-end requirements, there is a video on the Internet called gut opening, which takes about 15 minutes. This is relatively difficult and you don't recommend it for 12 years old. I suggest you listen to other opinions and adopt them in many ways according to your actual situation.

If you need me again, you can contact me at Baidu HI. I am not always online, but I will reply something. I have been working out for about 1 year.