Since its release the book “The Encyclopaedia of modern bodybuilding” by the one and only Arnold Schwarzenegger has been known as the bible of bodybuilding and the best reference guide to lifting weights. As a weekly blog I will post a bit of information for the book and I would strongly recommend that this is a book for anyone lifting weights.
-from bicep chapter
By altering your hand position on the bar you can change the way the Biceps are affected by the exercise. This kind of variation is great for developing weak points in the Biceps. For example holding the bar with a close grip puts extra stress on he outside of the head of the bicep.