In Lionel Shrivers entertaining send-up of todays cult of exercisewhich not only encourages better health, but now like all religions also seems to promise meaning, social superiority, and eternal lifean aging husbands sudden obsession with extreme sport makes him unbearable.After an ignominious early retirement, Remington announces to his wife Serenata that hes decided to run a marathon. This from a sedentary man in his sixties whos never done a lick of exercise in his life. His wife cant help ...