Lie on a mat, knees bent, feet flat on the floor. Grab a medicine ball with both hands and raise it over your head.

Slowly curl up until your shoulders and upper back are off the floor. Hold, slowly return to the starting position and repeat.

Have your partner stand directly in front of you. As you curl yourself up, throw the ball to her. Curl back down, then have her throw the ball back at your chest as you curl back up. Catch the ball, extend your arms overhead once more, then curl back down.
As you curl up again, twist your body and toss the ball to your partner to the left. Curl back down and catch the returntoss on your way back up. Curl back down, then curl and twist throwing the ball to the right. Alternate between all three moves (front, left, right).