"The little girl used to go crashing around the BMX race course at South Park, flying over mounds of dirt.
It was scary stuff, actually -- "In BMX, you can't be afraid of anything," she said -- but there were safeguards.
"You crash in BMX at less than 30 miles per hour, and on dirt," said Sinead Miller, who has been a dirt-biker since her Sesame Street years.
Her more recent focus on Olympic-style cycling -- races on both roads and velodrome -- means Ms. Miller travels faster and lighter, but it's a sport that carries its own hazards: "You're going 60 miles per hour on a descent; you could die."
Just turned 19, Ms. Miller, of South Park, is working on a career evolution. Everyone knew she was tough, and talented, on a bike, but she has speed as well, and just keeps getting faster.
Every summer, American sports fans with an interest beyond football and a cable subscription to Versa can spend hours marveling at televised coverage of the Tour de France.
The grueling event represents a more extreme end of the roadracing spectrum. Women don't race in this particular event, but Ms. Miller shares the riders' pain.
She been a national-caliber rider since her early teens, when she began showing up at the Wednesday night races on the Washington Boulevard oval track in the East End.
"I remember this skinny 13-year-old girl coming to area races to compete against the men and women and simply refusing to give up, even when it was a struggle," said Luke Dembosky, a lawyer from Shaler who has ridden with Ms. Miller on the UPMC team.
"We all smiled to see someone so young, so determined, but after a couple of years, we weren't smiling so much," he said. "She began beating all of the women and then taking on and beating many of the men."
Ms. Miller turned pro as a dirt biker at age 15, while attending South Park High School, where she also ran cross country and played basketball. But the latter were just keeping-in-shape diversion, something to do when Pittsburgh roads were snow-covered and treacherous.
"I was trying to juggle road racing and BMX. The summer I turned 17, I decided to focus all my energy on road racing."
At this time last year, she had plans to attend Penn State University. A phone call from the cycling team coach at Marian University in Indiana changed all that.
Marian, a small Catholic school with a big reputation in riding, has its own velodrome.
"I don't think any other team in the country can walk out of the dorm room and train across the street," she said.
The Knights men's and women's teams have won their share of national titles, but Ms. Miller would provide a first: she took the Division I women's criterium title last May in Fort Collins, Colorado.
A criterium is raced in a loop over relatively short courses.
Ms. Miller arrived at the nationals fresh off a European tour, where she was part of a U.S. team that competed in events ranging from 86 to 50 miles.
"They don't have criterium in Europe, so the races are a lot different," she said. "Everyone is a lot stronger, and the races are a lot harder.
"There were usually pretty hilly races and some very good women. Actually, one race had 200 women in the field, which is crazy compared to the amount of riders [in the U.S.]."
She picked up a lot of pointers in Europe, a victory in a race in Bordeaux, France, but also a bronchial infection. Going into the collegiate nationals, Ms. Miller was not feeling great.
"Even after that, for about a month, I was sick for a while," she said.
The collegiate nationals comprise a number of individual and team events. This criterium was contested over a .9-mile, figure-8 course.
University of Florida's Jacquelyn Crowell led racers into the final sprint, but Ms. Miller caught her right at the end.
She is known for her vicious sprint and strength. Many cyclists aren't wild about weight training, but Ms. Miller, who grew up around weights through BMX, said she enjoys it.
"I am getting stronger, doing better every year."
Mental focus and maturity, said Mr. Dembosky, are among her assets: "When we have indoor training sessions as a team, Sinead is one who is all business, not chit-chatting and goofing around like the older men on our team.
"She knows what she has to do to be the best, and she is disciplined and determined enough to do it, even as a teenager."
Ms. Miller said she is taking in the big picture, as far as her career goes. She is currently without a racing team, having left one in March, which puts her at a disadvantage in a sport where teamwork often is everything.
"It makes it tough, but it's taught me to be able to think on my feet, be more technical about my positioning in the peloton.
"Every second, every pedal stroke will count."
Making the U.S. squad for the 2012 summer Olympics in London involves two years of qualifying races, so she's getting ready for that.
"I'm going to start doing world-caliber races and acquire experience," she said. "I'm still young, there's still a lot of time.
"I think 2016 is more realistic for me, but I'm definitely going to work as hard as I can. But if it doesn't happen [in 2012], I'm not going to be down."
Although she was home on familiar roads this week -- on Monday, she took an "easy" two-hour ride from South Park down to the Mon Valley back through Mingo Creek Park -- Ms. Miller was to race again in Charlotte, N.C. this weekend.
The national criterium championships begin Aug.15 in Downers Grove, Illinois, so that's on her to-do list. Then it's back to school.
"Before I came into school, I had never raced on a track before. I still kind of think of myself as an amateur on the track, and even on the road," she said.
"I'm still young, I just turned 19. Most of the women who are best in the world are 30."