Start in a bridge position with your back on a physioball. Lift and straighten your left leg so it's off the ground and pointing directly in front of you. Raise your right arm over and behind your head, then swing that arm down to your side as you lift your left arm over and behind your head. Continue swinging your arms for all reps, then switch supporting legs.
Sets/Reps: 2×5 on each side.
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