MANCHESTER, N.H. (AP) – Red, white and blue posters tacked to utility poles leading up to the home of racewalker Joanne Dow read “Go Jo” and “Beijing 2008.” Because after years of setbacks and health problems, the 44-year-old mother of two has walked her way onto the U.S. Olympic team.

It only took knee surgery, a hysterectomy to remove a tumor and four Olympic trials.

“I just couldn’t believe it finally happened,” Dow said when she returned home after winning the 20K Olympic qualifying race at the Olympic track and field trials in Eugene, Oregon. “It was overwhelming.”

Fifteen years ago, Dow didn’t realize racewalking, which is like power walking with rules, was an Olympic sport.

Racewalking requires athletes to have one foot on the ground at all times, and the knee must be straight as the heel strikes the ground. That’s to prevent walkers from accidentally breaking into a run.

“When you normally walk, you never straighten your knee,” said former Olympic racewalker and columnist Tim Seaman. “But with race walking it’s a requirement. That’s what makes it technically difficult.”

Dow, a former college swimmer, believed she was just a very fast walker. But her fitness walking class instructor recognized her speed and persuaded her to teach the class. At a noncompetitive walking event in Boston, she was introduced to the sport and Manchester racewalker Bob Ullman.

“He said if you had started this earlier you might have been an Olympian,” said Dow, the oldest athlete on the American track and field team.

That comment fueled Dow’s competitive spirit.

At a racewalking clinic, a coach told her if she committed to training she could be one of the top female racewalkers in the country. Her husband assured her that he and their children would support her.

In 1996, Dow finished 10th in the U.S. Olympic trials. Two years later, she won the women’s national championships.

But then her left knee started bothering her. Doctors found a calcium growth rubbing against cartilage and operated. She didn’t resume training until two months before the 2000 Olympic trials. The then 36-year-old finished fourth.

She switched coaches and kept going, winning the bronze medal at the 2003 Pan American Games.

A year later, the pain began.

Doctors found a fibroid tumor growing inside her uterus. They wanted to operate, but Dow wanted to compete. Sick and bleeding, she raced in the 2004 Olympic trials. She came in second place – still not good enough to make the team.

So instead of going to Athens, Dow focused on getting well after doctors removed her uterus.

Four years later, another Olympic trials – her fourth.

This time would be different. Dow took the lead early, hanging on to win in one hour, 35 minutes and 11 seconds, earning a trip to Beijing.

“She’s the best athlete I’ve ever coached,” said her coach Robert Hoppler, a University of New Hampshire track coach. “Her strength is her mental toughness.”

Dow, however, credits her husband, 18-year-old daughter Hannah and 16-year-old son Tim.

“Nobody gets to this point by themselves,” said Dow, a part-time yoga instructor who has coached her children’s high school track and field and cross country teams.

Now, she’ll continue her training regimen of walking 50-60 miles a week, weightlifting, yoga, massage and physical therapy to prepare for Beijing.

“Recovery and me being older is something we’ve had to adjust for,” Dow said. “I can’t train like I’m 25. My body doesn’t recover as it used to.”

Though she plans to racewalk after Beijing, Dow said she’s done with Olympic trials.

“I’ve achieved my dream, so I’m not sure what would motivate me four years from now to feel like I needed to do it again,” she said. “My goal would be to be top 25 at the Olympics – which is top 25 in the world.”