(CNN)Willing her wheelchair up Heartbreak Hill, Olympic legend Tatyana McFadden had a rare moment of doubt.
Olympic great Tatyana McFadden goes for two marathon wins in a week
"I didn't think I was going to make it" McFadden told CNN in an exclusive interview, referring to the notorious ascent 20 miles into Monday's Boston Marathon. Her feet were frostbitten from the freezing rain and she was trying to overcome powerful headwinds.
"I was kind of slipping and sliding in the rain. My clothes were wet, so my arms were heavy so it just made for a very slow marathon," McFadden said.
But she did make it, going on to win the women's wheelchair division in Boston for the fifth time, setting the stage for Sunday's London Marathon where she will be trying to win back-to-back races in the space of less than a week.
"Having them six days apart you have to kind of recover and rest as much as possible and try and get your body back into doing another marathon," said McFadden, who is trying to win the two races back-to-back for the fifth time. "It will be really tough but I like challenges."
That's an understatement for the 28-year-old McFadden, who breaks barriers for a living. She's earned 17 Paralympic medals, including 7 golds, and won 22 major marathons.
She couldn't compete in the London marathon last year because she was recovering from surgery after suffering life-threatening blood clots in her legs. She regained momentum this fall, finishing first in both the New York and Chicago marathons.
Winning world class events at will has earned McFadden high-level endorsements from Nike, Coca-Cola, and BP.
She's also the face of a new innovation contest, launched by the Toyota Mobility Foundation. The foundation is offering $4 million to inventors who can help people with paralysis live more independently. Entrants already include a group developing an autonomous, eye-controlled wheelchair and a wearable exoskeleton that can aid paralyzed limbs.
McFadden has helped raise the profile of the sport, securing more access, media attention, and prize money for disabled athletes.
It's a life unimaginable considering where she came from.
Born with a disease called spina bifida, which paralyzed her from the waist down, McFadden still remembers the first six years of her life, spent in a Russian orphanage during the fall of the Soviet Union.
Without a wheelchair, she would scoot around on the floor, walking on her hands. In the orphanage, she found her life motto. "Ya sama" is a Russian phrase that roughly translates to "I can do it myself."
"I've always had that attitude," McFadden said. "I wanted to be independent and didn't want anyone to help me. I wanted to figure it out myself."
Deborah McFadden, a former U.S. Disability Commissioner under George H.W. Bush, and her partner, Bridget O'Shaughnessy, adopted Tatyana and brought her to the US.
"They found the local sports community, they helped me get into my first Paralympic games. Everything I've wanted to do in life, they've always said yes," Tatyana said.
Deborah helped write the landmark Americans with Disabilities Act, which prohibited discrimination against the disabled. Growing up in suburban Baltimore, Tatyana herself became a fierce disability rights advocate, suing the state of Maryland for the right to compete in high school sports.
"Here is somebody who is a champion, but it's more that she's a winner at the game of life," said Deborah McFadden, Tatyana's mother and manger -- nicknamed "Mom-ager" for short. "She's a role model for so many."
McFadden said she wants to be recognized as an elite athlete and not for overcoming a disability. Expect more challenges, more barriers to be broken and more medals.