The Twist: Squeezing a ball activates your inner thighs. Lie faceup with ball between ankles, toes pointed, and arms extended at sides, palms on the ground. Extend legs straight over your hips. Slowly lower legs toward your head until they're parallel to the ground. Hold and squeeze the ball 5 times, then roll back down, lowering legs 45 degrees from the ground. Return to starting position.