At 33, Torres is practically a senior citizen in the world of swimming; one of her training partners was a toddler when she swam in her first Games. Now she’s trying out for her fourth Olympic team. “Come on, Granny!” her coach teased her in practice. The joking stopped when Torres broke the world record in the 50-meter freestyle in June. “There is a myth in swimming that you have to be 17 or 18 years old, you peak and that’s it,” Torres says. “But I guess I’m peaking now.”

Torres isn’t the only oldster among this year’s prospects for swimming medals. If everything goes as expected at the Trials, America’s most promising Olympic swimmers will be a group of women who have already collectively won more than a dozen Olympic medals and who are closer to 30 than to 20. Torres’s toughest U.S. competitors in the 50- and 100-meter freestyle are veterans Jenny Thompson and Amy Van Dyken, both 27. If 33-year-old Angel Martino swims the relay in Sydney as well, the average age of the U.S. women’s tag team could be 30–a first. “To take on that kind of training at that age, oh my God,” says Mary T. Meagher, 35, who set the world record in the 100-meter butterfly when she was 16. Mary T–as she’s known–retired from swimming at 23. Last year, at 26, Thompson finally broke Meagher’s long-standing record. Of all the athletes the United States is sending to Sydney, these swimmers are among those with the greatest chances of winning gold.

Over the years, some older athletes–both male and female–have made stellar appearances at the Games. Twenty-nine-year-old Gail Devers won the 100-meter-dash at the 1996 Olympics–the same year Michelle Akers, 30, helped lead the U.S. women’s soccer team to victory. But swimming has been one of the last frontiers–a sport dominated for decades by high schoolers. Swimming’s sweetheart, Janet Evans, was not quite 17 when she won three gold medals in 1988, and in 1996, the average age of the women on the Olympic swim team was just under 20.

So why the sudden dominance of the 25-and-over crowd? Some suspicious minds raise the specter of drugs. These swimmers are not just performing at a world-class level, some people say, they’re blowing old records out of the water. Dutch swimmer Inge de Bruijn, who turns 27 soon, this summer crushed Thompson’s new world record in the 100 butterfly by more than a second–almost unheard of in a sport measured in 100ths of seconds. “Inky”–as De Bruijn is called–also set world records in the 50- and 100-meter freestyle. Despite suspicions about drugs, De Bruijn has never had a positive test result and vehemently denies drug use. The top U.S. women deny drug use as well.

Others credit improved technology–like the new hydrodynamic swimsuits–and better training techniques. A decade ago, Olympic swim training meant eight hours a day in chlorine. Now swimmers do much more cross-training. Richard Quick, the Stanford University and Olympic women’s team coach, trains Torres and Thompson. A typical day includes two to four hours in the pool, as well as some combination of weight training, spinning classes and flexibility training, such as Pilates or yoga.

Torres actually had to relearn her stroke. After a seven-year break from swimming, she jumped into the Stanford pool last year and swam two lengths, old-fashioned, windmill style, before Quick stopped her. “Dara, we don’t swim like that anymore,” Torres recalls him saying. He taught her the latest in stroke technique: looking at the bottom of the pool and putting the power at the beginning, not the end, of the stroke.

Torres also had to adjust to her older body. As people age, they need more and more time to recover from arduous activity. Quick once ordered Torres to sit on the couch and watch TV after she ran eight miles on her day off. Torres also has her own personal “stretch gurus” who work over her muscles for more than an hour before and after each race. While the younger swimmers chat on deck, Torres lies poolside while two men walk on her back in their socks.

Amy Van Dyken says she’s “a lot smarter about training” than she used to be. Instead of going all out every practice, she paces herself. “I’m not the young kid who was trying to show off for everybody.” It was decathlete Dan O’Brien who challenged Van Dyken to chase another Olympics, even though she’d already won four medals in Atlanta. At 34 he was trying again; why not Van Dyken? “You’re a wimp!” he told her. That did it. Van Dyken, who stands 6 feet and weighs 160 pounds, lifts weights with football players including fiance Tom Rouen of the Denver Broncos. She can bench-press 180 pounds.

What older swimmers lose in flexibility, they gain in mental toughness. Van Dyken has always been among the fiercest mental competitors, grunting loudly on the blocks and spitting pool water in opponents’ lanes. But she’s learned over time that mental edge is about staying focused. A false start might shake up a less-experienced swimmer, Torres agrees, “but I just chill. I never had that calmness when I was younger.” Ironically, age has given Thompson not just perspective but enthusiasm she hasn’t had since she was a child. With Columbia University Medical School awaiting her, she knows that there is life beyond swimming. “When I started swimming at 8 years old I did it purely for the love of the water and going to swim meets and eating Jell-O out of the box,” Thompson says. “I’m going back to those values.”

The most obvious reason swimmers are willing to spend more years in the pool: money. In the old days financial support meant free air fare to a big meet–but only if you won it the year before. There were no Title IX scholarships, no corporate sponsorships. Today most top swimmers have endorsement deals that don’t necessarily make them rich, but allow them to spend their day in chlorine rather than in staff meetings. Companies and sports associations are beefing up their sponsorship and prize money as well. After Van Dyken won four medals in Atlanta, Speedo more than tripled her contract. She also landed two big advertising deals, the Wheaties box and the “Got Milk?” campaign. At Sydney, if a swimmer wins a gold medal, she’ll earn $15,000 from the U.S. Olympic Committee and $50,000 from USA Swimming.

Still, Torres could have made a lot more money if she’d stuck with her day job. She had just landed a modeling contract in New York and finished her second infomercial as the spokesperson for the exercise craze Tae Bo. But she was too hungry to give it up. “I am more competitive now than I’ve ever been in my life,” she says. As Torres–and the other old ladies–barrel down their lanes this week, they are clearing a path for women who hope to go for the gold even after they’ve started to go gray.