In reading Mark Singleton’s Yoga Body , I’ve been fascinated by his central argument: that the yoga most of us practice today—Hatha, Vinyasa, Ashtanga, Power Yoga, and other movement-based forms—did not descend in a straight line from ancient traditions. Instead, the familiar, fitness-oriented yoga of modern studios took shape primarily in the early 20th century , especially between the 1920s and 1950s , through a remarkable cultural exchange between India and the West. Singl

If you're here, odds are you've either hit up a few yoga sessions or you're mulling over the idea. But in the midst of downward dogs and...