Competitive roller skating originated in the early 20th century, but in just the last few years took off in its modern form. Women have popularized the sport through theatrical costumes and performances, spunky nicknames, and “tough-girl” body slamming similar in aggression to football tackles — all on roller skates. Every player has her own stage name or alternate identity like “Pixie Hollow,” “Jo Hurt,” “Ivana Thrasher.”