swimming is actually a great idea! too bad that it's quite time consuming (the pool is not very close from my work/home and it's not cheap either) it's kind of moving :) sometimes it's the down middle forearm, sometimes it's closer to the elbow (both up and down), sometimes it's in the wrist... it also gets much worse in wet and cold weather
hmmm, looks yummy :D I might invest to see if things get better and start the exercise/working out after that...

I see you used the term forearms as in the plural. This was obviously a mistake so I took the liberty of correcting your post.

I came acroos this link the other day, it seems to be a collection of exercises. How good any of them are suited for you I can not say, but maybe you can find one that appeals to you and is right for you on there. I would advise you to ask your doctor for his ok before starting any workout to avoid picking a workout that is not suited for you and therefore might worsen your condition instead of improving it.

http://www.livestrong.com/forearm-exercises/

Maybe take up rowing or canoeing?
Join a team, helps the motivation :)

I used to row for 6 years in my youth (5-7 days a week). Still miss it till this day. Wonderful sport right out there in nature. Combination between physical excersize and mental concentration (technique plays a big role). Besides training your underarms, your whole body will get a workout. So better prepare yourself for gaining some abs as well ;)

whoa, Shaolin Monk Forearm Exercise!!! master the skill of iron arm! sounds awesome :D

Lol...not the one I was aiming at ;) scroll down the page and check some of the more gentle ones out.