STARTING POSITION:
Select the appropriate weight of the dumbbells. Lie on a fitball facing down, it should be under your stomach. Your feet should be touching the floor. Grab the dumbbell with your right hand and put the arm on the fitball. Use a supinated grip.
MOVEMENT:
Contracting your biceps, fully bend your right elbow while you exhale. Make sure you only move the forearm. Return to the starting position in a smooth movement while you inhale. Repeat the movement for the specified amount of repetitions and then repeat with the other arm.
TIPS: The exercise key is quality over quantity. The trick is to perform the exercise using proper form.