Women's rights campaigner Kathrine Switzer was attacked by an official who tried to remove her from the Boston Marathon in 1967 - Boston Globe

Her body buckles as it is wrenched backwards; her face grimaces while other runners her stare incredulously at what is happening barely a mile and a half into the 1967 Boston Marathon.

The now-iconic photograph of Kathrine Switzer being physically assaulted by race official Jock Semple made headlines 50 years ago, when she became the first woman to officially enter and run the 26.2 mile race - despite the fact that women weren't officially allowed to take part until 1972.

On Monday Switzer, now 70, will return to the start line exactly half a century after that picture was taken following a lifetime of campaigning for the rights of millions of other women to compete in the same long distance events as men.

Before 1967 and since its inception in 1897 - making it the world's oldest annual marathon - the Boston Marathon was strictly men-only. The only woman to have tried to complete it was Bobbi Gibb who, a year before, dashed out of a bush and over the finish line.

Kathrine Switzer has founded Fearless 261, named after her original bib, in partnership with adidas to encourage women to run Credit: adidas More

In 1967, Switzer registered officially under a gender neutral name - K.V. Switzer - was given a bib with the number 261 on it and wore a baggy grey tracksuit that ensured preoccupied start line officials assumed she was “just one of the guys”.

Despite the attempt to drag her off course, she finished in 4 hours 20 minutes. But it would become a life-defining event for the 20-year-old Syracuse University student.

“I wasn’t trying to make a political statement, I just wanted to race,” she says, her voice still full of verve, down a phone line from her home in the US. “He came up behind me quickly, grabbed me by my shoulders and tried to pull my bib off. He pushed me screaming, ‘Get the hell out of my race.’”

She escaped and spent the following miles mulling over inequality within the sport and how she could change it.

“I made the decision to finish no matter what. I would have finished on my hands and knees at that point. That was the definitive change, I’d gone from embarrassed and terrified to radicalised.”

Runners approach the finish line of the 120th Boston Marathon in Boston last year Credit: AP More

But change wouldn't come easily - it took Switzer another next five years to persuade the Boston Athletic Association to allow women to run in the Boston Marathon. In 1977, she created the Avon Women’s International Running Circuit, arranging 400 races in 27 countries for more than a million women (though earlier this month, women in Iran had to stage their own marathon after being barred from taking part in an official one, at the last minute).

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