Hold one side in an isometric contraction while the other arm moves through a dynamic (concentric and eccentric) movement. You then switch sides.
This simple modification not only helps you to create a new training stimulus, it also creates muscular overload by increasing the time under tension (TUT). By increasing TUT, you increase metabolic stress, a key mechanisms for growth.
"Back in the days of being 297 pounds, every workout was brutal; there was no other alternative. That's not the case any more. Have I become soft, like a former all-star playing out a multi-million dollar contract?"