First of all, it should be clear that the main purpose of boys' fitness is to strengthen their strength, and having developed muscles is their ultimate goal, while many girls are pursuing perfect bodies and have no such great demand for strength training. The gap between men and women in lower limb strength is very small, so there is little difference between men and women in lower limb training. However, there is a great difference in upper limb strength between men and women, so there will be obvious differences in training for this.
First, chest training: the wider the boy's chest, the better. Therefore, the most suitable action for boys to practice chest is push-ups. However, if it is not standardized, it will have no effect. As for girls, their breasts can't be enhanced by exercising pectoralis major. If girls want to practice their breasts more intensively and straightly, they can try dumbbell bench press.
Second, back training: for boys, the back should be thick and wide, which is more masculine, so boys have quite high requirements for back training. For girls, if the back is too wide, it will appear "crouching", so the focus of girls' back muscle practice lies in rotator cuff muscles, lower and middle trapezius muscles, rhomboid muscles and so on.
Third, arm training: Men and women have completely different training goals for their arms. Men show their great strength in order to develop the muscles of the upper and lower arms. Girls have completely different requirements for their arms. Girls have a more detailed attitude towards triceps brachii. What girl doesn't want her arms to be long and thin?
Indeed, because of various factors, men and women will have different fitness methods, methods and purposes. But in daily life, there is actually no gap between men and women in sports and fitness.