He used to train at the same gym as me. He had amazing hamstrings! He was my idol when I was natural. I trained naturally for 8 years. I'm not sure his workout routine, but his diet was pretty much all chicken breasts and white rice with some nuts.
I was introduced to him by my buddy dave who he was friends with.. Nice guy.. Talked for a bit.. Very small guy except for the quads and hammies.. From what I saw it was your typucal 3 sets of 8 to 10 and three exercises or so per bodypart.. Saw him train chest and back.. But wasn't watching everything.. Now if you asked my buddy dave Id Jean paul was natural or not dave absolutely believed he was.. But said the others of that era ( Mike Ashley etc) were not..