Ive been working out on and off for the past couple years, but starting around of this year, I've been on a bulk system with lots of eating and high intensity low rep workout. My only supplement is whey protien mixed with a tall glass of milk.
The good news is that my weight has increased from 170 to 195 (6'3") and my max bench from 135 to 170. My chest, back, and base of the neck have gotten visibly stronger and bulkier.
The bad news is that my arms have not gotten any bigger, despite doing the bench presses twice a week and occasiaonal bicep/tricep exercises. My upper arms still look kinda scrawny, and my thumb and middle finger still slightly overlap when i place them around my wrist, indicating a thin wrist.
I've always been an ectomorph, weighing as little as 150 until age 21 and 170 until only very recently, all the while at 6'3". I was always pretty weak too. My pants still fit just as well now at 195 as they did at 170, which on the surface is a good thing, but indicates that only certain parts of my body are growing, which applied to my arms turns into a bad thing.