Men out there, if you ever hope to get nice looking guns, you need to familiarize yourself with the dumbbell curl. It's certainly not the only arm exercise at your disposal, nor should you limit yourself to it when you want to work your arms, but most people who have successfully built their arms place this particular exercise prominently in their personal training routine.

To perform this exercise, grip the bar so your hands are about shoulder width apart. When you pull the bar up, bring it up as far as you can. But make sure your biceps are doing are doing most of the work. Some make the mistake of pivoting their shoulders to do part of the movement. At the peak of the movement, flex your biceps. Giving your arms a solid flex before going down for another rep will maximize the effectiveness of the exercise.

One of the troublesome things about this exercise is that it is really easy to cheat without even knowing it. Some lifters unknowingly cheat by failing to make a full extension when they bring the bar down. Others lift with a slight hunch, which makes your lower back do some of the work. Show your personal trainer your form to make sure you are getting the most benefit from this exercise

You also shouldn't limit yourself to the standard barbell curl for bigger biceps. Any good trainer well tell you that doing the same exercise the same exact way might hinder your development, because some muscles might get missed or get too accustomed to a particular exercise. You should also throw in some dumbbell curls, such as the alternate dumbbell curl or incline dumbbell curls, to get some arm workout variety.