I’ve endured many cycles of success and failure in my long struggle with healthy eating and consistent exercise. Whenever my efforts fail, however, it’s because I’ve succumbed to the allure of something that seemed to offer me true pleasure: another slice of apple cake with fresh maple frosting or a series of leisurely mornings where I don’t have to drag my body out to the road for another run. The truth, of course, is that poor nutrition and a lethargic body yield nothing good at all.