Lying on the ground doing crunches might help you tone your upper six-pack, but you also need to strengthen your abs standing, because that’s how you use them in your daily activities. Here is a great ab and core exercise, and all you need is a medicine ball and to know how to write your A, B, Cs. There are two variations. To start: Grab a medicine ball that’s between five and 15 pounds. Stand with your feet shoulder-width apart, making sure your knees are

not locked. For stability: Start with the ball at chest level, and slowly write the cursive alphabet in front of you. While your arms move around in all sorts of angles, you need to use your abs to keep your torso still. Think of keeping the area between your ribs and pelvis solid. For a more advanced version, try this move while standing on a BOSU . Learn the other variation.

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How-To: Alphabet Abs With Medicine Ball