Hang on the rings with your legs in L, use the force of your lats to place your legs in perpendicular position with respect to the ground, in that position make a hip extension to hang upside-down, perpendicular to the ground, repeat steps in the opposite way to complete a repetition.
triceps, chest, shoulders
triceps, chest, chest, biceps, back
buttocks, calves, femoral, quadriceps
biceps, dorsals, core