STARTING POSITION:
Sit on the floor, place your upper back on a fitball and your hands behind your head. Contract your pelvic floor and core while keep your body straight.
MOVEMENT:
Slowly breathe in through your nose and open your elbows at the same time. Breathe out through your mouth and close your elbows. During the exercise, try to breathe filling the abdomen and the rib cage.
TIPS: You shouldn't feel pain during the exercise. If you feel fatigue, stop and rest.