"The heavy-smoking novelist Martin Amis has become an ambassador for Pilates, a boring-but-fashionable system of exercise that involves repeated tightening and relaxing of the pelvic floor muscles. This is good news. The masses have long lapped up exercise tips from celebrities whose glowing and healthy looks they admire. But Amis does not resemble Jane Fonda or Geri Halliwell. In fact, as the years pass, he looks more like W. H. Auden, who famously compared his creased and wrinkled face to 'a wedding cake left out in the rain.' My Pilates class may soon get less crowded."