Not all cavemen are in the past. The Modern Caveman Movement involves men in urban gyms, grunting and sprinting on all fours, lifting heavy stones, and running barefoot. They're eating a Paleolithic diet of meat, often raw, with no grains or beans or bread or dairy. 72 year-old Arthur De Vany is an economics professor whose physical accomplishments could awe a 20 year-old. He tells Anne Strainchamps it's all about mimicking what our cavemen ancestors would have done.