You also will need to get some gear, which is where newly thriving companies such as See Jane Run, TeamEstrogen.com and SkirtSports.com come in. Capitalizing on the fact that most tri outfitters are oriented to men, these women-only oases offer guidance geared toward a woman's body and her sense of aesthetics.
Lori Shannon founded See Jane Run in 2000 after feeling neglected by clerks. "I'm short and a bit overweight, so because I didn't look like the marathoner that I am, I was ignored in those stores," she says.
That same feeling was the spark for onetime elite triathlete Nicole DeBoom. Tired of "looking like a boy" at her tris, DeBoom, who is married to male tri star Tim DeBoom, last year launched Boulder, Colorado-based SkirtSports, whose Triks ("skirt" backward) line of gear was aimed at feminizing the female triathlete. Her stock sold out fast. "The biggest surprise was the buyers," she says. "I was sure it was going to be 20-year-olds, but my new target demographic actually is the 40-year-old multitasking mom."
Add educated to that list. DeBoom, who was a competitive diver for Yale University, says that tris "seem most compelling for Type-A type women who are very good at juggling things. I'm amazed by how many are ex-Ivy Leaguers."
Not just for 20-somethings
Smart, athletic and defying middle age; USA Triathlon, the sport's governing body, reports that nearly a third of its 20,000 women members are 30 to 40.
"Many in this crowd are the first generation of women who got to play competitive sports in college" and now find themselves craving both the camaraderie and competition from those days, says Shannon.
"The other big group is what I call the Oprah generation," she adds. "That's the 50-plus crowd, women who have been told they can do anything. Besides being a great overall workout, a triathlon does have the mystique. It's empowering."
That's exactly what Dawna Stone is hearing from female triathletes when they call in to her new fitness-oriented satellite radio show: "The self-worth you get from a triathlon is amazing. Complete one, and you feel you can do anything."
Stone credits triathlons with keeping her fit and focused. The former collegiate swimmer-turned-marketing exec took a gamble two years ago and started Her Sports magazine; more recently she was Martha Stewart's winning Apprentice, which has led to her new Martha-branded radio show.
"A growing group of women want to push themselves in the ways they did before marriage and kids," says Stone, who is training for a summer tri. "They aren't saying sports comes above family. But they are saying, 'We need something for ourselves.'"
Back at the hilltop track in Oakland, all that's missing is the Sister Sledge anthem We Are Family. There are a lot of backs being patted and encouraging words being shouted. The women assembled here defy stereotypes; some are model-lean, others are not. Some are single, others are single moms such as Barbara Caruso.
"I have two teens, and at first, they were really skeptical about me doing this," says Caruso, 51, a corporate communications executive from nearby Piedmont. "But, wow, what a turnaround. They're so proud now. As for me, I have a new view on aging. What's 50? I see women in tris who are 70."
As Caruso stretches out, triathlon newbie Phillips wraps up a sprinting exercise. She's winded but can't suppress a grin: "What can I say? I guess I never realized I could be this strong."
Just then, See Jane Run trainer Rebecca Whittaker claps her hands and issues the latest directive to the group: "OK, ladies, I want another lap, the first half slow, the second half at 80 percent. Let's do it!"
And in a flash, these tri warriors are off, leaving jobs, boyfriends, husbands, kids and other anchors of life in their determined wakes.
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