Sit down on a preacher bench and rest your elbows comfortably on the pad. Grab a hold of the dumbbells and hold them with your palms facing down (reverse grip). This is your starting position.
Lift the dumbbells up until your forearms are almost completely vertical. Then lower them back down to the starting position. Finally, repeat the 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 on the downward portion of the movement; always keep some tension for optimal movement efficiency and muscle development
SPECIAL NOTES & LEVEL of DIFFICULTY VARIATIONS
To increase the level of difficulty, slow down the movement or use heavier dumbbells.
This is a good intermediate to advanced level exercise for your forearms. It also impacts your biceps as the secondary muscle group. When performing this exercise it's important to remember not to rush this movement. Jerking the dumbbells up may put excessive strain on your forearm muscles and tendons. Thus, nice and easy is the way to go!
In addition, keep in mind that you may feel some soreness in your lower biceps and well as forearms after you perform this exercise for the first couple of times. This is perfectly normal. Once you do this exercise for a few weeks, your forearms will feel much stronger and more resilient.