Tone Your Muscles Faster With These Stability-Ball Moves

Here's a great one for toning the tush and backs of the thighs.

• Start by lying flat on your back with an exercise ball under your heels. Bridge your hips up, and hold that position through the entire exercise.
• Flex your feet and dig your heels into the ball. Place your arms straight out to your side for support — don't use them, though; they are just for support.
• Slowly roll the ball toward your body as you curl your heels. Keep your hips in the bridge position; don't thrust them toward the ceiling as you do the move.
• Then slowly return to the start position (straight legs, hips bridged) to complete one repetition.
• Do three sets of 12 to 15 reps.