Compulsory gymnastics consists of specific routines that the gymnast must learn exactly. This is done in gymnastics levels 1-5. USA gymnastics created the routines with the goal that the gymnasts have a strong gymnastics foundation before advancing to the optional levels. All of the skills in compulsory gymnastics are progressive. So after a gymnast learns the level 4 routine and masters it, the level 5 routine will build on the skills she has just mastered.