Stability Ball Bridge Exercises
Stability balls make good balance-training tools because of their inherent instability. The inflated plastic sphere's tendency to roll in any direction at the drop of a hat forces your core muscles to engage constantly to keep it from rolling out from underneath you. Once you've mastered regular glute bridges -- which help counteract the chronic hip-flexor tightness and gluteus muscle laxity many sedentary people suffer from -- you're ready to do bridges on the ball.
