I know exactly what you are talking about. This pain is like shin splints in your forearms. I have found through the years that this pain comes and goes. It’s more of a progressive injury that seems to happen over time. The major causes of this are both sloppy form and strict form. In both instances you are going against your body’s natural bio-mechanics and inviting this injury.
So how do you deal with it? Sometimes just simply changing your grip position will take care of it. The pain will subside and it will transparently heal. This is the best case scenario. Usually you won’t be so lucky. Above all, make sure you are training correctly. Straight bar curls should be a fluid movement. Eliminate excessive jerking but at the same time don’t be overly strict and ridged during the exercise. I would also recommend using Biofreeze Gel or some similar rub on your forearms before and after training.
If the pain does not subside with these changes you might want to try taking about a week off from training. During this week off rub some Biofreeze Gel on your forearms 3 times daily. This stuff works wonders for injuries like this.
One last thing, never abruptly release your grip from the bar after you complete a set of curls. When you finish your set, release your grip from the bar slowly. This little trick alone has rid many lifters of these forearm shin splints.
