Lie face-up on the floor holding a pair of dumbbells just outside your shoulders. When your upper arms at 30-45-degree angles with your torso, press the dumbbells straight up just as you would with a standard dumbbell flat-bench press. Stop just shy of locking out the elbows, then slowly lower the dumbbells until your upper arms touch the floor. Go right into the next rep.
START: Grasping two dumbbells, lie with your upper back on an exercise-ball with your feet planted firmly on the floor. Hold the dumbbells just outside your shoulders with your palms facing forward and your elbows out to your sides.
MOVE: Forcefully press the one arm up in an arc (coming inward at the top) until your arm is fully extended above your chest. Reverse the motion, being sure not to lowering the dumbbell below chest level. Repeat the motion with the other arm.
Start on the right side by holding your palm out in front of you, as if you were motioning someone to stop. Pull your right arm back, while maintaining the hand position, until your palm is by the side of your lower chest. Extend your left hand like you're going to shake hands with someone, then bend your left elbow to bring your left palm to meet your right. Pull your right shoulder blade back and down, and stick out your chest as you use your right pec to push your right hand into your left with as muscle force as you can muster while you resist the right hand with your left. Take about 5 seconds to complete the positive (concentric) portion of the rep and another 5 seconds on the negative (eccentric). Do 5 reps in this manner, then repeat on the opposite side. Go back and forth until you've completed 3 sets of 5 reps for both sides.