shoulder and upper arm pain

I've been fitted at a couple of bike shops, and it is interesting to see different methods. Rather than lay down more cash, I'm seeking input on where I could adjust my fit to cause this pain to go away:

I like to be at the hoods for the majority of my ride (apart from the usual hand-changing on the bars throughout a ride/climbing, etc.).

After an hour or so, I'm getting pain near the shoulder blade (starts creeping toward the lower neck as time goes on); mostly on the right side.

I'm conscious of having my elbows bent throughout the ride and a loose grip. After 5 hours in the saddle there's no pain at the hands.

I can ride in the drops for half-an-hour, with no lower back pain at all.
178cm/60kg

As time goes on, I also develop muscle? pain in both arms at the upper arm (before the elbow), underneath.

Have a short torso and long inseam.

My stem is 100mm, set at 6 degrees, below zero.

Could shortening the stem to 90mm be a possible solution?
(I've already got a 73mm reach bar)

I'd be curious to know some history. Why did you opt for the second fitting. Was it because of this fit issue? If so, what did they adjust to correct for it, and.. did it help or change your level of discomfort?

What I'm getting at is... it's important to track history, any changes made and their effects (if any) on the fit issue.

Because you offer that the discomfort is mostly on the right side, at least two things may be contributing factors. One is that you aren't riding in perfect symmetry (most of us don't). This may be due to poor form and/ or arm length discrepancy.

Another thing to check is that your saddle is level (I tip mine slightly up). If you find yourself periodically pushing back on the bars to reposition yourself, I'd say it's a distinct possibility (and would explain your upper arm pain), but not the only one. Reach could be excessive as well.

Also, just because you bend your arms and keep a loose grip doesn't mean you're keeping your upper torso relaxed. You may still be pulling your shoulders up towards your neck, which would lead to similar symptoms. Try to be aware of that and keep relaxed.

If you're comfortable doing so, it helps to do some on bike stretches - one arm at a time behind your back/ roll your head (loosens neck muscles), roll your shoulders. I think changing hand positions more frequently will help as well.

These are some general things to think about and consider as possibilities as you ride. There are fit/ form solutions for this and I think once you (or your fitter) determine the cause (or causes) you'll be able to remedy your fit issue.

Thanks.

I had a second fit due to the first guy setting me up with a racing style fit i.e. seat way up (according to my second fitter), and was getting leg pain issues.
I don't race; my style is more French fit (the bike geo I chose).

The second fitter lowered my seat, which fixed the leg pain.

I've had my bike for about three/four weeks now, with regular riding. I did notice when riding my previous hybrid bike that I tended to ride with my right shoulder up.
Since riding my new bike I've made sure that I'm relaxing my right shoulder, but this tendency could still be causing some of the pain, I suppose.

My seat is level, and I would say that I don't tend to push back into position.

I suppose its ok to get back in contact with my second fitter, to explain the issues?
Hopefully he'll be ok with me going back to him.