Hmm, interesting, thanks for the question - I'm stumped! But always glad to think about details of pain types, because it helps pinpoint, understand and influence it, instead of being overwhelmed by believing it's "everywhere, all the time, moving, unchangeable".
Can you describe the form of pain?
I was thinking a dull Ache all over like I get from & after exertion. But maybe it's more localized and stabbing?
And is it not actually from the exertion (so more in the muscles) but from the movement (so more in the tendons)?
I think we can all relate to achey pain getting worse from walking, but I don't think any of us can say it's just on the front.
But thinking about it, I do think my Ache is always more in my quads rather than my hamstrings, and in my biceps rather than my triceps, is that praps what you mean?
I'm just detailing that I get my overall Ache in my limbs from exertion, which builds up during it, but can vary if I'm using my arms more. I've started calling this post exertional malaise, like in CFS. But that made me realize that I also wake up at night and in the mornings with an overall Ache in my limbs that is similar, but different, and what I've been lying on hurts, which in the case of my usual "relief posture" seems more the fronts of one leg and one arm.
Whilst when I walk, the Ache is mainly in my legs, starts after 1-2 minutes and continues for quite a time afterwards. But I can get a bit of relief pausing every few minutes. And I get local pains in my elbows and knees. However while cycling I don't feel the Ache while doing so, it surges in when I stop; and my local pains are more in my wrists & I think my tailbone, my knees only if I cycle for a long time on a lower saddle. But I spose in both walking and cycling from the tendon insertion points around my joints, almost always the issue of my local pains.
Which brings me to the questions if your arms hurt while walking, or when, if what you describe as "tops/fronts" is more around the joints (tendons). My arms used to hurt quite a bit from using them overhead or with kitchen work, so I had to pause regularly, but that has got better.
Now I've got quite a bit of my physical energy back since 1 week, I'm curious how well I can now walk.