A football league meant to rival the NFL shattered the glass ceiling. There’s a reason you may have never heard of it

For several years in the 1970s, full-tackle women’s football teams, including the Houston Herricanes, competed in the short-lived National Women’s Football League. A new film tells the story of the diverse cast of characters on the Texas team who paved the way for future generations as they stormed the field, writes Sheila Flynn