Yeah Arnold was huge in 6th day. He flexed his bi in the mirror at one point of the movie and it was huge. I didn't think he was still that big. He must still be working out, at least before he does movies.
The director (and several other people on the set) said that he had a normal trailor and a trailor of just weights for him to use everyday before work and throughout the day. It sounds like he is still woring pretty hard
He still trains hard and I bet he does some juice every now and then too. This guy has made his life off of the stuff since day 1, there's no way he would want to give it up. In the 6th day he is very big and it looks like he has a little gyno going on.