Performing the: A Step-by-Step Tutorial Dumbbell One Arm Pullover on Exercise Ball
Slowly walk your feet forward while rolling down onto the ball until your upper back and shoulders are comfortably resting on the ball, your body forming a bridge, with your hips lifted and aligned with your body.
Hold the dumbbell with both hands above your chest, keep your arms straight but not locked, and slowly lower the weight in an arc behind your head while keeping your hips and chest lifted.
Pull the dumbbell back up in the same arc until it's directly above your chest again, keeping your arms straight but not locked.
Repeat the above steps for the desired number of repetitions, then switch to the other hand and repeat the process.