Joseph Baena was back at it on Instagram, offering his more than 245K followers a look at some of his new workout routines. The 23-year-old lookalike son of Arnold Schwarzenegger took to the social media platform on January 27 to show his fans what an average chest and back day at the gym looks like for him. The series of videos highlighted each intense workout, starting with a clip fo Joseph, sans shirt, doing pull-ups.