STARTING POSITION:
Select the appropriate resistance in the weight stack. You need to place a bench in front of the weight stack to do the exercise. There should be a cable of a low pulley. Grab it with your left hand and with a neutral grip. Place the right foot in front of the other and your right hand on the end of the bench for support. Your upper body should be parallel to the floor. Contract your pelvic floor and core while keeping your chest facing the floor. Retracting the shoulder blade, pull the cable to the side of your chest. The forearm should be perpendicular to the floor.
MOVEMENT:
Using your triceps, fully extend the elbow until the arm is parallel to the floor while you exhale. Return to the starting position in a smooth movement while you inhale. Repeat the movement for the specified amount of repetitions and then switch sides and repeat with the other arm.
TIPS: The exercise key is quality over quantity. The trick is to perform the exercise using proper form. Make sure you do all the repetitions in all the range of motion of the exercise.