Rowing, as viewers are reminded several times in Sarah Megan Thomas’ belated-coming-of-age tale, is the only sport where you win by going backward. So perhaps it’s fitting that the film feels like a holdover from another era. It’s an uncomplicated single-character study whose main purpose is as a housing for its lead performance. Director Ben Hickernell (Lebanon, Pa.) is a thoughtful presence behind the camera, but Thomas, credited as writer, producer, and executive producer, is the obvious auteur, orchestrating a star vehicle she lacks the screen presence to anchor.

Unfortunately setting herself up for comparison against Reese Witherspoon’s thorny ex-Olympian in How Do You Know, Thomas plays an Olympic hopeful who, after twice being named to an alternate slot, and with her 30th birthday closing in, quits the team and drags herself home to Philadelphia, hitting up former flame James Van Der Beek for a coaching job at her high-school alma mater. Even as she reintroduces herself to the joys of staying out past 9 p.m. and indulging in the occasional alcoholic beverage, she attacks her new teenage charges with a mixture of encouragement and incredulity, adding additional practices with a matter-of-fact air that suggests they can go hard or go home. “With improvement,” she says after one unlucky rower catches an oar in the Schuylkill River, “that could have been terrible.”

The school’s eight-oared boat is a lost cause, but Thomas sees potential in Alexandra Metz and Meredith Apfelbaum’s scull, enough to make it to the national championships at the Henley Royal Regatta, the terminus of Thomas’ own rowing career. But since Backwards is more about Thomas’ mental fitness than her rowers’ physical condition, the film skips the training montages in favor of Thomas telling the genial Apfelbaum to “come angry tomorrow,” or honey-lit flashbacks of Thomas hitting the ergometer, with her late father watching critically, clipboard in hand.

Even for those who’ve never set foot in a shell, Backwards is full of keenly observed details: the way a crew’s synchronous movement begins with tipping the boat into the river, or the waterlogged shoes that result from a particularly bad practice. But Thomas doesn’t invest her story, or her performance, with the same level of detail, and her mother (Margaret Colin) is a champagne-tippling caricature. Races are won by going backward, yes, but when the oars don’t move in sync, the boats don’t move at all.