i have a few years of training under my belt and my biceps grew explosively at first and then the size quickly slowed down and in the last year they about stopped growing and never get sore (slowly got stronger though).
But yesterday i had an arm day and today I am going HOLY **** i did something right, I can't remember the last time my biceps have been this sore.
it was a bicep/tricep workout, this was the bicep portion:
preacher curls w/ ez curl bar: 125*8, 135*8, 145*8, 155*5
dumbell curls seated on incline: 55*10, 60*10
spider curls: 75*10-15 reps or so *3 sets
Now I always start biceps off lifting super heavy and that works for strength but the spider curls are what did it. Spider curls are an awesome exercise for biceps with a huge ROM and I never ever (EVER) see anyone doing them. Certainly helped me out. They feel really good moving across that big range of motion too.
I just thought i'd share. I've trained my biceps hard for a while and never gotten them this sore. Definitely keeping the spider curls in my routine.