SETUP: Place one hand and knee on a bench, flattening your back (not hunching). Take a light dumbbell in your spare hand and pull your elbow tight to your side to create a 90 degree angle at the elbow. This s your starting poisition.
REP: Push the dumbbell back & up, trying to straighten your arm behind you, and squeeze your triceps like they owe you money.
TIP: For extra difficulty, start the rep by bringing your elbow slightly HIGHER than the line of your body and trying to push back & up at a diagonal angle. This will create even more tension.