of all the muscle groups i workout, it seems like my back is the hardest to get sore. (my upper and lower lats to be more specific) it always seems as though my arms give out before i can get a good back workout. i've been trying to concentrate on form and go down with the weight, but it seems like nothing works. is it possible that my arms are just too weak for me to get a good back workout?? does anybody else have this problem??