Support your forearm on a bench or box behind yourself, lean to one side to support on your leg, or hinge forward at the hips, and hold a small plate in the hand with the thumb down—this is usually easiest by sitting down and leaning forward to get the forearm at around a 45-degree angle relative to the floor. Keeping the wrist and forearm aligned, use a controlled speed to move the weight as far down as possible, and then as far up as possible.
 
Purpose
The wrist ulnar deviation is a simple exercise to strengthen the wrist; it should be combined with radial deviation.
 
Programming
Generally sets of 8-15 reps are appropriate.