yeah - I meant maybe limit it a bit --- as for the "pump" - I would expect the hand muscles to pump up more than the arm as you play -- if not, then I think there might be some basic technique issues to be examined. I find that, these days, unless I have been working some drill to exhaustion, when my LH begins to pump, it usually means I'm being a bit too "grabby" in my LH as I play.
I think there's probably a sort progression/refinement as one begins CG (I'm not talking down dark, so please just ignore this if it does not apply in your case). As one begins working LH technique, I would suspect that beginners probably feel forearm soreness - followed by hand cramps - and, eventually, swelling in the base joint and segments of the LH fingers. THINK (though I could surely be wrong) that we shoot for using our fingers rather than our entire LH or left forearm. When we have the major work done in and by our fingers, we are approaching that point where the fingers just sort of dance on the fret board and strings (if you know what I mean)
NOW! none of this
is to say that I don't get some hellacious barre cramps while trying to play limosna at half or quarter speed