You have to really love horse racing--and English horse racing at that--to appreciate this comeback memoir about a cancer victim turned Grand National champion. Co-author Powell is racing editor of London's The Sunday People, so it's natural for him to take every hedge with jump jockey Bob Champion, both before and after the bout with cancer. There are other problems too: though Champion's hard work to get back in shape for racing is commendable, he otherwise seems a not-very-remarkable, and not always likable, fellow. He moans through the admittedly gruesome side effects of six chemotherapy cycles, spewing abuse at those who stand by him. He also maintains a stable of girlfriends, so that ""a constant worry"" during hospitalization ""was the rotation of his dozen or so heartbroken girlfriends so that any two of them should not meet, let alone clash, sad-eyed at his bedside."" The one idea that motivates him during his chemotherapy confinement is racing again--and winning the Grand National on a horse named Aldanti. A leg injury nearly sidelines the horse for good--but both mount and rider manage a halting return to racing, and eventually the world-famous 1981 triumph. Powell tells Champion's story with near-adoration, while Champion interjects a more modest opinion or reminiscence now and then. Overall, for Champion groupies only--and it's difficult to believe there are many in this country.