It's hard to imagine, but there was a time in America, not too long ago, where people frowned on women participating in large-scale athletic events. I'm not talking like today, where no one really watched the WNBA. I'm talking straight up discrimination against women who were competing in the most mundane of sports, like long distance running.
So, running a marathon isn't mundane to the person running it, but it's not like we're talking about a woman doing Greco-Roman wrestling with dudes in the '50s or anything. It's running, for crying out loud.
In spite of the tame nature of the sport, Kathrine Switzer was harassed during her 1967 Boston City Marathon run as she became the first woman in history to complete the race.