It was on a dare from friends 15 years ago that Alexander, who never played sports as a child in Long Beach, Calif., entered his first triathlon. Though "I thought I was going to die," he hung on to finish—and was hooked. Observes two-time triathlete of the year Mike Pigg, 34, who has competed against Alexander: "He always is in a good mood."
Although Alexander, 53, has yet to shed any significant avoirdupois from his exertions and often finishes dead last, he and his wife of 30 years, Marilyn, have plenty to smile about. With a blood pressure of 110/70 and a resting heart rate in the 50s, Alexander "definitely is my fattest, fittest patient," says Dr. Craig Phelps, who as physician of the NBA's Phoenix Suns sees his share of big men. "Dave is one in a million."
Turkey thinks so and has made Alexander an honorary citizen. In Malaysia he enjoyed a private dinner with a sultan. "People all over the world know Crazy Dave," says Alexander, who has accumulated 600,000 frequent-flier miles. "But I would give up everything just to finish in the middle of the pack."
VANISHED WITHOUT A TRACE
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