Add Yahoo as a preferred source to see more of our stories on Google. Man doing a box jump in a crossfit gym Crossfit is growing in popularity; not only is it brilliant for increasing your overall ...

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This article was reviewed by Craig Primack, MD, FACP, FAAP, FOMA. "Right to the core," "core values," and "hardcore." These little idioms highlight just how vital the concept of "core" is in our lives ...