Rachel McAdams puts her all into her roles. She’s not about to let her male costars outpace her.

Recently, when shooting an intense and physically demanding scene for True Detective, Rachel McAdams was all about keeping up her energy, being in top shape for the part. But something went horribly wrong.

“That one took about five days,” Rachel McAdams said. “That was pretty intense. I actually puked during that scene. When I was running and reloading my gun—it actually wound up being about 200 yards, it was like two football fields—and I was just going all out and we did it a couple of times.”

Did McAdams end up picking up a virus on location?

“It was my own fault,” she explains. “I had been drinking that Emergen-C and going hard to just try to keep my energy up. Not a good combination, the running and that. But I kind of felt badass. Like yeah, let’s do it again. It was really fun though. I like action. I like being thrust into that.”

My god Rachel McAdams in #TrueDetective is incredible. @skyatlantic

— Tom Davis (@BigTomD) July 17, 2015

Then there was Rachel McAdams’ commitment to her role in Southpaw. While Jake Gyllenhaal certainly had to stay in shape to play a boxer, McAdams was hitting the heavy bag on set, too.

“I figured [my character] Maureen would understand boxing really well. She’d make it her business to know it. Jake came and watched me box in the ring. I just tried to pick it up. Nowhere near the extent that Jake did. It was an excuse to sweat and get in shape. It’s a total head to toe workout – you do one three-minute round and you’re toast,” McAdams said.

I could watch Rachel McAdams movies forever

— sweet miss (@HisSweetMiss) July 17, 2015