United Kingdom, April 15 -- Arnold Schwarzenegger "pushes" his bodybuilder son Joseph Baena in the gym and makes sure he doesn't "slack off".

The former Mr. Universe's 28-year-old son - who he fathered with his former housekeeper Mildred Patricia Baena - has followed his father into the world of bodybuilding and he recently won his first competition - and Joseph has now revealed his famous dad is a huge help during training.

In an interview with GQ , Joseph explained: "He's the best training partner. I don't know what to say ... He pushes me. He makes sure that I don't slack off in the gym. When the carbs are low and the calories are low and I start getting tired, he pumps me up."

Joseph also revealed his dad inspired him to get involv...