MUSCLES ENGAGED Abdominals The abdominal muscles (abs) provide movement and support to your core area. The deeper and closer to the spine the particular abdominal muscle is, the more effect over body posture it will have, and this often contributes significantly to a healthy back. Shoulders The shoulder is the most movable joint in the body. However, it is an unstable joint because of the range of motion allowed. This instability increases the likelihood of joint injury, often leading to a degenerative process in which tissues break down and no longer function well. Equipment Used Medicine Ball A medicine ball (also known as an exercise ball, med ball, or fitness ball) is a weighted ball roughly the diameter of the shoulders (approx. 14 inches). Medicine balls come in a variety of weights from 2lbs. to 30lbs. and can be made of hard plastic, dense rubber or synthetic leather material. Exercise Instructions Step 1 Start on your back with your feet about shoulder width apart while holding the medicine ball over your chest. Step 2 Press the dumbbell up overhead as you sit up in to a tall seated position. Step 3 Lower yourself back down to the ground and finish with the medicine ball over your chest.