Unlike his celebrity-competitors, Henderson makes no attempt to win converts to running, or to preach its virtues: this is just some up-to-the-minute advice, along with some informal discussion, for those who've found their sport. The alphabetic arrangement, moreover--A is for ""Approaches and Attitudes,"" Z is for ""Zest for Life,"" etc.--is just a peg on which to hang whatever Henderson wants to write about. And that, mainly, is that we've learned a thing or two from the explosion in running. For one, most people train too much: ""pace your entire career as if it were a long race""; don't exhaust yourself at the start. For another, the ideal shoe is probably one that doesn't provide a lot of cushioning, not vice versa. Henderson also has some lighthearted fashion pointers (""In for cool-weather training are long nylon pants. Out--baggy gray sweats. Way out--sweats with shorts on the outside"") and some solid tips on training (there are at least ten sure signs of an overstressed body, beginning with an elevated resting pulse). A knowledgeable, relaxed update for the inner core.