Both those guys were considered "big" by linemen standards in Knoxville at that time. They were always big kids in their age group. I went to the Boys Club at the same time as them, and they dwarfed regular sized me.
I still can't get over the fact that JaMarcus Russell grew up eating mainly mayonnaise sandwiches growing up because he was so poor. Genetics outweighs environment 9 times out of 10.