Upper Body Ergometer
"By far the best machine at the gym for shoulder stabilization, mobility, and muscle development is the UBE," says Minardi. "Use it regularly, and you'll see bigger, rounder delts." Since it's a spin bike for your upper body, you'll get cardio benefits too.
The Setup: Sit or stand at the machine, and adjust it so your shoulders are level with the handles.
How to Do It: Grip the handles and pedal with your arms, aiming for four minutes at level 2 with a speed of 80 RPMs.