Forearm pain & soreness...

I was wondering if anyone ever experiences forearm discomfort both during swimming and afterwards? I just turned 50 a couple of days ago and have been experiencing this problem off and on for a couple of years now. I normally swim 3500 to 4000 yards or meters 4 to 6 days a week (have been fairly consistant for the past 10 years). I'm hoping to pump up the training this year in order to do well at Worlds in August. This is so hard to describe but here goes: this pain/soreness/weakness is from the elbow down; usually my left forearm is a bit worse since it's weaker than my right. There's no numbness involved; the closest analogy would be a shinsplit to describe the feeling. There's no pain whatsoever if there's no pressure on either forearm. However, if I touch my chin with either hand and apply mild pressure, I can definitely feel it. The sensation seems to be located more towards the "inside" or "underside" of each forearm. The pain isn't intense and hasn't prevented me from training, but I am concerned. In the past, I've found that I can swim through it and I intend to start weight training next week. I also "ice" both forearms after every workout and this seems to help. I've talked to my coaches and many swimmers about this and no one's ever heard of my condition, so I decided to try this forum. If anyone has had a similar problem, I'd greatly appreciate hearing about your experience and how you dealt with it... Many thanks! Dave Schrader