Until the 1960s, it was deemed too "dangerous" for women athletes to run distances longer than 200m - and a marathon would kill them, or leave them unable to have children. Rubbish, of course. But when Kathrine Switzer signed up for the 1967 Boston Marathon, it wasn't the distance that bothered her - it was the enraged race director trying to assault her.   

Thanks to pioneers like Kathrine, women have made huge strides in long distance running - and are now challenging the times of men in the very races they were banned from for so very long.  

For a full list of sources, see the show notes at timharford.com.

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