Dado5,
I have that exact same thing right now on the top of my
right forearm. Not to the painful extent that you describe
(though I did many month ago), but pain in the exact same
area non the less.
Mine I believe, and the changes I made verify this, was due
to hours and hours of "mousing", using the computer mouse,
with my right hand while working in Photoshop, like for 8 - 10
hours a day. (I did not have the pain in my left arm.) That
coupled heavy barbell curls, which I suspect aggravated it.
This pain prevented my from doing any curling movements
what so ever. And no chin-ups, and I love chin ups and am
fairly proficient at them. Rows were okay, but I had to be very
careful with respect to form, reps and the selection of
exercises (which taught me much in retrospect . . . old dog,
new tricks . . .)
Now . . . what did I do make it go away (I am 90% now)?
Well, I tried having an ice wrap on my right arm while using
it mousing, which should have told me that what I was doing
was causing the problem, but it didn't. I'm pretty stupid
sometimes.
Some things that made it go away. First thing I did was
switch hands when using the computer mouse. That allowed
it to rest but also slowed down my work flow considerably
but I soon taught my left hand all my right hand moves.
I also took a month off from weight training, a forced layoff,
not due to the pain, but a month's vacation with my wife.
Most of the pain eventually went away, and what pain that
did remain was due to handling a very heavy dSLR camera
14 hours a day.
When I returned home, thinking it was healed enough, I started
mousing again with my right arm and weight training. Another
stupid mistake, at least in regards to the mousing was concerned.
The pain immediately retuned. Again, I switched arms and
adjusted my weight training routine. This helped, but it took a
while, and ever so slowly the pain got less and less, to the
point where I could do a select few curling movements: rope
curls with palms facing my chest (great exercise I was never
forced to try . . . and I like them very much now) and dumbbell
curls, very light, with no supination.
What got me just about back to normal (I have not tried chins
yet or barbell curls yet) is the application of "sport gel" with
arnica. Prior to that, I had tried a cream called Traumeel, a
homeopathic healing ointment, with zero effect. I had tried
Arnica before, in it's pure form when I had tendonitis from
rock climbing and it never worked. But when I tried this new
gel called Muscle Therapy w/ arnica (mfgd. by Hyland's . . .
a free plug) it made a very noticeable difference, and only when
I applied it in huge amounts twice a day, and let it dry there,
forming thick, unsightly glaze. Usually I poo-hooed, was very
skeptical about these sorts of homeopathic remedies, but
I think this one really works for me. You might want to give
it a try.
Things are about back to normal now. I am very careful now in
the gym. I am very cautious about introducing new movements
that might aggravate it, and do so starting out with a very light
weight. I am now back up to 30's for curling and increasingly
heavier select curling movements in conjunction with pulldowns
which give me a great pump with no pain. I like the results so far.
Hope this helps . . .