(NEW YORK) -- You don't have to carry a club or wear a bearskin to live like a caveman. To keep fit, a number of people have adopted the "Paleo" lifestyle -- eating and exercising like our ancestors from the Paleolithic era.
Art De Vany, 73, is often called the "grandfather" of the Paleo movement. For De Vany, a workout includes pulling his Range Rover in his driveway. He compared it to "hauling heavy bison out of a pit."
De Vany, the author of The New Evolution Diet, also eats like a caveman by consuming meat, seafood, vegetables, and fruit, but no grains or processed food. He adopted the caveman or Paleo diet some 30 years ago in an effort to improve the health of his family.
The human species during the Paleolithic age, he said, "was probably the epitome of the expression of the human genotype. (They had) large, powerful brains -- they gave us all that we have in our world."
Those big-brained cavemen ate meat, vegetables and nuts. What they didn't eat, besides processed foods, was bread, grains, rice or anything that is the product of agriculture.
Actress Megan Fox is rumored to be a fan of the diet, and experts seem to have no major problems with it because it balances meat with a lot of fresh vegetables.
Robb Wolf is another adherent to the Paleo lifestyle. Wolf, the author of The Paleo Solution, runs a gym in California -- but it's not your average gym. The gym's equipment includes gymnastic rings, pommel horses and cargo nets for climbing.
"We're not scratching around under bushes and getting poison oak on us in weird places and stuff," Wolf said. "It's trying to make full-body, functional movements that are fun."
"We do it in a group format," he added. "I think a lot of the success for my gym and a lot of gyms like it is there is a tribe element to it."
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