Hypertrophy is muscular volume increase. Density increase is hyperplasia IMO. It's argued that steroids only aid in hypertrophy while IGF-1 can create hyperplasia.
the jury is still out on igf-1 (it does do what you claim, but i mean its efficacy in bodybuilding) , but HGH definatly gives you a grainer, more dense look...............i have seeen it occure with many many guys, and myself as well........
but guys with grainy muscles..............guy
s like rich gaspari, yates, paco buatista............that is mainly genetic, like veins........
also, muscles often get a denser look with time.................you often hear people describe it as that "old man" muscles when referring to bodybuilding.