In an exuberant social media post, Zac Efron showed a first look at the impossibly muscular physique he built to make himself ring shape for A24’s upcoming The Iron Claw. Since Robert De Niro got himself into ring shape to play Jake La Motta in Martin Scorsese’s 1980 classic Raging Bull, it has become a badge of pride for actors to at least once put aside the pasta and wine, and hit the gym with fitness and fight trainers, severely alter their diets, and ingesting who knows what else, to get into ripped shape to be believable in the ring....