I started riding seriously last summer. By spring I was down from 200 to 180, but had lost upperbody strength and general size. (No more showing off the pecs.)
(My right wrist started giving me problems back in August, slowly my bike got to be dusty. Numb, popping... painful after 25 or so miles. Mainly it started bothering my ability to do mechanical repairs (Part of my job) with loss of strength in my fingers... and extremely sharp, drop the wrench type pain.)
I've kept at the same level of weight training, no real change in rep's or weight (See wrist) but since august I have most of the strenght/size back.
Why is it the more biking I do the more it seems my upper body muscle disappears?