In the 1970s, she made history while running in Boston and New York. She later fought to get a women’s marathon into the Olympics.

Ms. Kuscsik, who competed in more than 80 marathons over four decades, was in the forefront of the push to end the longstanding barriers against women running 26 miles in sanctioned races.

Overcoming male resistance as a voice for equality, she was the first woman to enter the New York City Marathon and the first official female winner of the Boston race.