A fascinating cultural history of fitness, from Greek antiquity to the era of the "big-box gym" and beyond, exploring the ways in which human exercise has changed over time—and what we can learn from our ancestors.We humans have been conditioning our bodies for more than 2,500 years, yet it's only recently that treadmills and weight machines have become the gold standard of fitness. For all this new technology, are we really healthier, stronger, and more flexible than our ancestors...