Jack Hunt-Borsma, 46, of Canada, has run a marathon every day since mid-January. That is, 42.2 kilometers in a day! The woman set herself this goal after losing her left leg to cancer.

This Saturday he completed his 104th marathon. Hunt-Borsma expects the feat to be certified by Guinness World Records. According to a media spokesperson, the process takes about three months.

The previous Guinness Record for women was 95 marathons. It was founded two years ago by Alyssa Amos Clark, a non-controversial runner from Vermont. She had chosen to run marathons as a coping strategy during the pandemic.

Spain’s ultra-racer Ricardo Abad holds the record in the men’s section. He is said to have run 607 marathons in 607 days. He finished the series in 2012.

Jack Hunt-Borsma is definitely feeling relieved. “Part of me was really happy,” she tells the BBC. “The other part thought I had to keep running.” Her body is also recovering from record hunting: “I feel better during the entire 104 marathons.”

It’s been 20 years since Dutch doctors diagnosed Jackie with what’s known as “Ewing’s sarcoma.” This is a rare form of bone cancer.

Within just two weeks, his left leg had to be amputated to save his life. She was only 26 years old. She recalls: “It was a roller coaster ride, everything happened so quickly.”

At first the young woman had trouble accepting what had happened. She was angry and she was embarrassed. She wore long pants in public to keep other people from paying attention to her prosthesis.

Jackie started running in 2016. She bought a special prosthesis for long-distance runners and signed up for her first 10-kilometer run.