12-year-old children, please don't do bodybuilding, the scope of fitness will be wider, I don't know what you mean.

Please refer to the sports in the physical education textbook. You can combine strength with aerobic sports such as football, basketball and badminton, which is helpful to increase strength and benefit heart and lung function.

Pure strength training is not recommended for you, it will affect your physical development.

I am still young, so it is enough to do more school sports, such as pull-ups and other horizontal bars, parallel bars and basketball. It helps me to improve.