01/06/2015 07:43 BST | Updated 01/06/2015 11:59 BST

92-Year-Old Cancer Survivor Harriette Thompson Becomes Oldest Woman To Finish A Marathon

A 92-year-old three-time cancer survivor has become the oldest woman to complete a marathon.

Harriette Thompson finished the 26 mile Rock 'n' Roll race in San Diego with her son Brenny in seven hours and 24 minutes.

Speaking of the key to her success, she said: "I guess the secret is just keep going and have pleasant thoughts."

Thompson, who has raised over $90,000 for the Leukaemia & Lymphoma Society, said "Every year I hit up all the people in my retirement home. I write them a thank you note and say ‘I think this is my last year,’ then I do another one.”

Although Thompson didn't run her first marathon until she was 76, she's no stranger to smashing records. Aged 92 years and 65 days, she took the oldest woman title from Gladys Burrill who ran the Honolulu Marathon in 2010, aged 92 years and 19 days.

Last year, she set the bar for the fastest marathon run by a woman over 90, breaking the previous time by almost three hours.

When asked about how she felt about becoming the oldest woman to run a marathon, Thompson modestly said: ”I guess it’s sort of unusual now,” she said. “But in 10 years it won’t be unusual at all. People are living longer.”