Among most important advances in sports technology, few can compete with the invention of the sports bra. Following the passage of Title IX in 1972, women’s interest in athletics surged. There was just one problem—actually, make that two problems: their breasts. Boob bounce hurts, as women getting in on the jogging craze found out. Then some friends in Vermont had an idea to stitch a couple jock straps together to build a contraption to keep things in place. Their creation revolutionized women’s participation in sports and launched what’s become a multi-billion-dollar industry. Today, high-tech boob labs are helping designers make ever more effective—and stylish—iterations, even for athletes with DDD cups. Outside contributing editor Florence Williams, author of Breasts, looks back at the game-changing invention, takes measure of just how far we’ve come, and points towards an even brighter, bounce-free future.