Lie faceup on the floor with your lower legs placed on a swiss ball.
Raise your hips so your body forms a straight line from your shoulders to your knees.
Pause for up to 5 seconds in the up position, then lower your body back to the starting position.
Swiss-ball Hip raise and leg curl
Lie faceup on the floor and place your lower legs and heels on a swiss ball.
Push your hips up so that your body forms a straight line from your shoulders to your knees.
Without pausing, pull your heels toward you and roll the ball as close as possible to your butt.
Pause for 1 or 2 seconds, then reverse the motion by rolling the ball back until your body is in a straight line. Lower your hips back to the floor.