A compulsion to exercise can sometimes do more harm than good. How fit is too fit? asks Tamar Adler.
For as long as I can remember, my mother was a casual runner. I could often be found on autumn and spring weekends of my Westchester childhood cheering at the finish lines of prim 5Ks. But in the year after my father died of cancer, a few months before her fortieth birthday, my mother began to train at our local gym with something like mania. I had never liked the gym. I found it intense and macho and loud. Nor did I, at fifteen, understand my mother—who was delicate and poised, with a fragile beauty—inside one. But that’s where she was, for hours a day, with a trainer named Tony, who told me when we first met that my mother was “a beast.”