While Natalie Dormer was getting ready to return to the small screen as Lady Margaery Tyrell in "Game of Thrones" season 5, the actress has also been busy getting in tremendous shape for "The Hunger Games: Mockingjay — Part 2." 

Lady Margaery looks like one meek and tame woman, but Dormer plays a completely different role in the final "Hunger Games" movie. People Magazine documented her talk with Self (April Issue) and there, she explained how important it was to be in good physical shape to play Cressida in the film. 

Cressida is part of the rebellion who is helping Katniss Everdeen rally up support from the people to fight against the Capitol. The war is coming, which makes it very important for the fighters to be in good shape. In fact, Dormer said that she's in the "best cardiovascular shape" of her life. 

"In Mockingjay – Part 2, I'm basically running around in heavy armor while carrying a semiautomatic rifle," she said. "I don't know how I would have kept up with [my costars] Liam Hemsworth or Sam Claflin if I hadn't been in the best cardiovascular shape of my life." 

Dormer continued to share that she got into shape without the help of a personal trainer, which is actually a surprise to hear. She narrated that she ran the hilly streets of Atlanta during the day, which is where "Mockingjay" was being filmed. At night, she would do hour-long interval workouts. Not to mention, she had to wake up at 5 a.m. every morning to film her scenes, including the battle scenes. 

Additionally, Dormer recalled that she also trained for the April 2014 London Marathon before she even signed up for her role as Cressida. Looking back, she couldn't believe how she did all of it. She also revealed that her green juice really helped, too. 

"When you have early calls, you don't necessarily want to eat first thing in the morning."

"Hunger Games: Mockingjay — Part 2" is set for release on Nov. 20. Meanwhile, "Game of Thrones" season 5 is premiering on April 12.