Chest/Triceps, Back/Biceps and Legs/Shoulders. The Holy Trinity of bodybuilding split routines. Nowadays the idea of split routines is so ingrained in the fitness community that the idea of whole body training for anyone other than a beginner is scoffed at. This is despite the fact that men like Eugen Sandow, George Hackenschmidt right up to Reg Park built their physiques using whole body routines. Something that begs the question…When did bodybuilders start using split training routines and why did they become so popular?