I feel pretty comfortable with my arms in terms of size 'height' wise (i.e. how tall they are when flexing from bottom of tris to top of bicep) but they have never seemed to really fill out and 'buldge'. Instead they remain skinny. I've heard of wide grip curls helping this to an extent, but find them rather difficult to manuever without losing grip, and I'll be honest I haven't done them consistently enough to really gauge progress. Are there any tricks to working the area in between the bicep and tricep to help fatten these arms out? I realize that I'm somewhat on the lean side, but that hasn't stopped other parts of my body from filling out with dedicated work.
I appreciate any input!