So This Is How Margot Robbie Got in Shape for I, Tonya

Brook Mitchell/Getty Images

Think your job is demanding? Margot Robbie's 2017 role as Olympic ice-skater Tonya Harding in I, Tonya didn't just require her to look the part-the actress also had to learn how to skate and improve her fitness to keep up with the physically taxing scenes.

"I spent a lot of time in the gym, trying to build muscle mass for I, Tonya," Robbie told Body+Soul before the Australian premiere. "Weights, mostly, and lots of sit-ups" formed the basis of her workout routine. "It's all the stuff you know you're meant to do, but just can never be bothered to do," the candid star admits.

Ice-skating was, of course, "a huge part of it," Robbie tells Popsugar. "I did as much as we could possibly do before production started. I think I did about three or four months of skating, like five times a week for a couple of hours a day," she says, admitting that the training left her in awe of Harding's skating prowess. "Even if I had 10 years to practice, I could never do a triple axel," she says.