Kneel down on the floor and rest your elbows and upper arms comfortably on the exercise ball. You will need to lean a bit forward to get in perfect balance. Then, grab the barbell with your palms up and at shoulder width apart. This is your starting position.
Raise the barbell up until your forearms are almost completely vertical. Then, lower the weight back down but don't fully extended your arms. You should always keep tension in your biceps. Finally, repeat entire movement for the desired or prescribed number of repetitions.
Perform this exercise in a smooth and fluid motion
Don't extended your arms completely at the bottom of the movement
SPECIAL NOTES & LEVEL of DIFFICULTY VARIATIONS
To increase the level of difficulty, slow down the movement or use heavier barbell.