Doctors once told her she would never play sports again, have children, or hold a regular job.
Karin "Kaz" Thorburn has just crossed the finish line of the Sydney Marathon, the 551st marathon of her life. As impressive as that sounds for a 59–year–old, the story behind the number is even more remarkable.
Karin Thorburn: Limited By Diagnosis Or Unstoppable
Thorburn was highly active from a young age and quickly established herself as a talented youth track athlete. Then, at just 12 years old, her life took an unexpected turn.
She was diagnosed with scoliosis and soon underwent major surgery, which left her with a steel rod supporting her spine. The operation itself was difficult, but what followed proved even harder: she had to learn how to walk and run again.
The medical outlook was grim. Doctors told her she would never be able to play sports, have children, or pursue a normal career.
Years later, after marrying young, Thorburn gave birth to her first child despite those predictions. That moment changed her perspective completely. If the doctors had been wrong about that, what else might be possible?
From Small Steps To Extraordinary Achievements
Thorburn started with short runs around the block while pushing her one–year–old son in a stroller. As her confidence returned, she began entering races and gradually discovered a passion for endurance running.
First came a 14–kilometer race (about 8.7 miles). Then the Gold Coast Marathon. Over time she continued to improve, running farther, faster, and setting bigger goals for herself.
What began as a personal experiment eventually grew into an extraordinary marathon career.
A New Challenge
At some point, running alone was no longer enough. Determined to push herself further, Thorburn learned how to swim so she could compete in triathlons.
That decision led her to complete eight Ironman events, each consisting of 2.4 miles of swimming, 112 miles of cycling, and a full 26.2-mile marathon.
She also qualified for and completed several major international races, including the prestigious World Marathon Majors in Berlin, London, Chicago, Tokyo, Paris, and Boston. She qualified for Boston at the age of 55.
In 2024, she completed 70 official marathons in a single calendar year, setting an Australian women's record in the 55–59 age category. One year later, she surpassed 500 career marathons, becoming the Australian woman with the most marathon finishes ever recorded.
Following her latest milestone at the Sydney Marathon, Thorburn now stands at 551 completed marathons. Her next goal is 750, while her long–term ambition is to eventually reach 1,000.
Social Media Presence
Thorburn is not a traditional influencer with massive sponsorship deals or hundreds of thousands of followers. However, she uses her platform to share her journey and inspire others.
Through her Instagram account @independentrunnerevents, she supports fellow runners and organizes endurance events of her own. One example was the "Magnetic 30in30" challenge in June 2024, where participants completed a marathon every day for 30 consecutive days, covering a total distance of about 785 miles.
What began as a diagnosis that was supposed to end her athletic future has turned into a career defined by 551 marathons, eight Ironman finishes, and a record no other Australian woman has achieved.
Karin "Kaz" Thorburn is a running example of determination and resilience. She not only proved her doctors wrong but also took control of her own story and found a sense of purpose along the way.
Today, she continues to inspire runners around the world, and it seems her extraordinary journey is far from over.
