Set up for the one arm prone hammer curl by setting an adjustable back bench to an angle of around 30-40 degrees.

Grab a dumbbell with your weakest arm (this is usually the left) and position yourself with your chest against of the bench (prone position).

Your feet should be used for stability on the floor, your shoulders should be about level with the top of the back paddingand your arm should be hanging - holding the dumbbell with an neutral grip (palm facing towards your body).

You can use the free arm for support.

Put the tension on your bicep by slightly bending your arm. This is the starting position for the exercise.

Keeping your elbow fixed, slowly curl the dumbbell up as far as possible.

Squeeze the bicep, and then slowly lower the dumbbell back to the starting position.

Repeat for desired reps, and then repeat the same on the other arm.

Exercise Tips:

Your elbow should be fixed throughout the movement. Only your forearm should be moving.

Keep the rep timing slow and control the weight.