Set up: Tummy over fitball, or in 4 point knee position on the floor. Shoulders down, set neutral spine (tilt forward and back, stop midway).
Set your core, ensure you switch on your pelvic floor (link back) and deep abdominal (link back) muscles at the same time. Lift one arm slowly in front of your body, raise to shoulder height. Return to start position, repeat with opposite arm. If able, progress by raising arm above your head, pelvic floor and deep abdominals must stay activated and spine needs to stay in neutral (if not return to arm at shoulder height). Relax and reset pelvic floor and deep abdominals between each repetition