Exercise has been good for us as long as anyone can remember. Prehistoric man did it (if we’re to believe Fred Flintstone). Sedentary activity produces lethargy, obesity, and disease. One-two-three, one-two-three builds strong bodies and minds. Frankly, when I was in school, I hated gym—and the gym teacher. The uniformity sought after by such exercise masters was anathema to my anarchistic character. Thank heaven for personal trainers. It’s one thing to march to the same son