The pec fly with resistance tubing is great for shaping and strengthening the chest muscles. The chest is scientifically named the pectoralis (hence "pec" fly). This muscle is used any time you push a chair up to the table, shut a car door, or push a shopping cart. There are two muscles that make up the pectoralis. They are the pectoralis major and minor. The pectoralis major is always the prime mover during chest exercises.
This version of the pec fly can be done seated or standing. It is called the pec fly because the arms "fly" outward and to the center. First, anchor the resistance tubing to any stationary object, preferably at chest level. Grasp hold of the tubing handles and lunge forward on one foot. The starting position is with your hands out wide. You should feel a stretch on the chest muscles. Once your hands are in position, bring them together toward the center, touch lightly, and repeat the exercise. During the fly, the elbows should be slightly bent and locked into position.
Anchor resistance tubing at chest level. Start with arms out.
Keep elbows locked into position. Bring hands to center. Exhale.
Return to the starting position and repeat several times.