Jogging and sit-ups are recommended, as well as some aerobic exercise. Will not grow muscles, but also play a slimming effect. Aerobic exercise will not affect the height and development, on the contrary, it will help the height and development. Don't be anaerobic, just like the pull-ups downstairs. It is difficult and requires high physical strength, which has a great impact on your development. Practice abdominal muscles well, and do it every day when you have time, because abdominal muscles don't need rest time to buffer like other muscle groups. Persistence is victory, but abdominal muscle training is a protracted war, and you can't fish for three days and dry the net for two days. Otherwise, if you practice your abdominal muscles for a month, you will recover every other month without practicing. Finally, eat less junk food and high-fat food. Drink more water. Finally ..... gone.