“Becoming a champion is easy; staying one is hard,” we are told in the new trailer for “Platform,” a documentary about women martial artists in Iran.

Described as a “‘Rocky’-esque tale of determination and grit,” the film charts the journey of three sisters — Shahrbanoo Mansourian, Sohelia Mansourian, and Elaheh Mansourian — as they train to compete at World Championship level in Wushu.

The trailer offers a brief look at the sisters’ grueling training sessions, and hints at the challenging societal expectations they face as women and the struggles they have endured. “I wasted my childhood working for a better life,” one of them explains.

Directed by Sahar Mosayebi, the doc has a comprehensively women-led team around it, with industry veteran Mahtab Keramati among the film’s producers.

“Platform” won The Discovery Award at Raindance Film Festival in 2019. It opens in theaters and virtual cinemas July 9..