YOUTUBER and fitness coach Bradley Martyn is a fitness influencer and self proclaimed gym rat. The influencer has almost five million followers on Instagram as of March 2023, but who is he and how did he become famous? Who is Bradley Martyn? Born on May 22, 1989, Bradley is an online fitness influencer and coach from California. He began his own training program called BMFit in 2006, and later dropped out of college to pursue his fitness dreams.