The realisation that 110,000 people had turned out to watch what she did at Little Athletics each weekend, became the spark that ignited a 20 year career.

Breen, then 10 years old, and her family attended the first morning session of track and field at the Sydney Olympic Games in 2000.

Even then, among a spiraling Mexican wave, she knew she was part of something bigger than sport. And that Olympic spirit drove her to become the fastest Australian female sprinter in history.

"That was a grounding experience for me and has stayed with me for the past 20 years," Breen said.

"It's what motivated me throughout my career to make it at the Olympics. I knew from then on that was exactly what I wanted to do, I just had no idea of how I was going to do it.

"I wasn't the most talented of the children but I loved running and the pursuit of getting the best out of myself. I think, definitely, being there and immersed in the Olympic spirit gave me that drive and ambition to achieve it myself.

"It's so special and I wish I remembered more about the athletes competing. But I remember very much the atmosphere and feeling like I was part of something much bigger than myself.

"It was so much more than sport, it was people coming together and I think in today's society that seems like such a different memory. It's really challenging but I feel very grateful to have been a very small part of something this country did."

Breen went on to become a two-time Olympian, compete at three Commonwealth Games (Delhi, Glasgow and the Gold Coast) and at four world championships.

Her journey from the Sydney stands came full circle in 2014 when she smashed Melinda Gainsford-Taylor's 20-year-old record, stopping the clock at 11.11 seconds in the 100 metre sprint.

MORE CANBERRA SPORT

Gainsford-Taylor ran fifth in the 200-metre final at the Sydney Games alongside Cathy Freeman, who placed sixth after winning the 400-metre gold medal.

Breen remembers watching the finals from her lounge room and was inspired by having two Australians in the 200-metre race, saying it was special to take the record of her idol Gainsford-Taylor.

"Those women were so resilient and inspired the next generation, and still many athletes now. It's such a great gift to give," Breen said.

"To take that baton from Melinda was really special. She was a very similar body-shape to me in that sense, blonde hair, a big build and a strong female.

"To break the record she set when I was three years old was amazing. I only hope my record hangs around for that long. When the next Aussie comes along to break that record, it'll be a really exciting time for sprinting in Australia."

Breen, 29, announced her retirement from athletics in July, saying it was the right time for her to finish instead of chasing a third Olympic berth in 2021.

She's still involved in athletics as a coach and is working at Lifeline Canberra, where she sees herself for a long time yet.

"I'll always be involved at the track but honestly, I'm not missing training at all, which sounds odd because it had been my life for so long. It's been really nice to give my mind, my body and my soul a break after 15 years," Breen said.

"I'm grateful it's come full circle to be able to feel good in myself to not do anymore. For a long time it did scare me and I'm very lucky to have found a place where it's now the right thing."