When Lyn Lemaire was just a little girl, her father boasted that his only daughter could "catch a ball in the dark." Lyn did not grow up to be a shortstop. Baseball, however, is one of the few sports that Lemaire, now 28, does not excel in. She has swum in national competition, played varsity basketball at UCLA, run marathons, rowed in top meets and in 1976 set the U.S. women's record for the 25-mile bike race.

Then, last January in Hawaii, Lyn entered the most grueling athletic event of her life. It was the second annual Iron Man Triathlon, a unique test of endurance in which competitors swim 2.4 miles, bicycle 112 miles across Oahu and run a 26.2-mile marathon—all in the same day.

The competition began at dawn—Lyn finished the swim although the ocean swells hit six feet and the wind gusted at 60 mph. Before the bicycle race she bolted down a tuna fish sandwich and then nearly got sick. After 23 miles in the marathon, she hit the wall and wanted to give up, but didn't. By the end of the day the indomitable woman had placed fifth in a field of 15—and the other 14 athletes were all men.

"I don't care if I lose," says the 5'6", 148-pound Lemaire. "I like having something to train for, a goal."

Born Eleanor Lynette ("I always hated pink things and Eleanor was pink") in Santa Monica, Calif., Lyn thinks of herself as "fairly independent," a virtue she attributes to her parents' divorce when she was 4. "It comes," she says, "from not being able to depend on things." By high school she had entered four national swimming championships. At UCLA, she graduated Phi Beta Kappa in biochemistry in 1974 and played all three positions in basketball. As a senior she tooled off on an 18-day, 1,500-mile bicycle trip from Vancouver to Los Angeles. The next summer she pedaled around England and northern Europe, but still had no interest in competitive cycling. "I thought people who raced on bikes were silly because they had to train so hard," she says. "And I didn't even know women did it."

The next year, after moving to Massachusetts, Lyn joined a bicycle club. In 1976 she set the 25-mile record of one hour eight seconds. Now her day is one long training session. Leaving her two-story red clapboard house in Wellesley, Mass. at 6 a.m., she rows her scull on the Charles River for a couple of hours. Most afternoons she runs six miles, cycles 32 or rows again. All that exercise works up an appetite, and Lyn admits to being a junk-food fiend ("It's hard to find bean sprouts on the road"). She rarely drinks and then only to get tipsy—"mainly good beer and margaritas."

Though she's not dating anyone at the moment, Lyn hasn't "ruled out marriage and kids. I like men, I'm not a separatist." Adds Ed Pavelka, editor of a national bicycle racing magazine, "She's respected and liked by other women on the cycling tour, which is not too normal. I've never heard anyone say anything bad about her."

In September, financed by insurance money from her father's death in 1976, Lyn will apply her energies to Harvard Law School. But next January there's another Iron Man tournament, and, if women's cycling becomes an event in the 1984 Olympics, Lemaire might be coaxed into it. "If I don't like being a lawyer or sitting in an office every day," she says, "I might bag it and become an adventurer. It's my Walter Mitty idea."