Originally Posted by
JiveTurkey
I don't think swapping to an aluminum bar will help--especially if the current bar is steel. Look into better grips, like Ergons.
+1
Even if one bar is more flexible than the other, getting flexy bars is a bad idea anyway. They'll flex every time you stand up to pedal, try to put power down, etc. You want your headset/stem/bar system to be as stiff as possible, that's why threadless headsets are a real improvement over threaded systems.
If you want more cushion get wider tires and make sure you're not inflating them too much. Also realize that if your hands/wrists/arms/etc are getting sore your fit is probably wrong. Stiff bars are not the cause.