SIT-UPS WITH STRAP
Attach strap so that and fix the carriage so that the strap it is hanging at the height of your abs.
Grasp the hanging strap with both hands. Legs are bent.
Pull the elbows towards the knees. Upper body curls in. The position of the arms relative to the upper body remains unchanged.
Especially in the beginning, perform the exercise very slowly, until you have mastered the sequence of movements.