Many bodybuilders end up with a weakness in forearm muscle development because they don't train forearms right from the beginning of their bodybuilding workout. Another reason for forearms lagging behind, aside from the obvious one of bone structure, is failing to execute the forearm exercise correctly and in a strict enough manner. The more you isolate the forearms muscle and force them to do the movements without any help from the upper arms, the more your forearm muscles will respond. This means being very strict in your forearm workout.

An important technique for bringing up lagging forearms muscle is one-arm training. Forearms muscle that are used to working together to curl a barbell will often be shocked into accelerated development when you force them to lift and control a weight on their own. Dumbbell wrist curls and Dumbbell reverse wrist curls are two of the primary exercises for accomplishing this. Additionally, doing cable work one arm at a time not only forces each forearm muscle to work independently, but to work against a different kind of resistance as well. For this kind of workout, we recommend one-arm cable reverse curls.

It is also necessary to pose and flex your forearms as often as possible - not just when you are training them, but between sets of arms, chest, back, and shoulders as well. Your forearms muscle will have to be flexed every time you hit any kind of pose in competition, so you might as well get used to it. And the effort of contracting the forearm muscle like this will also accelerate forearm development.