NEW YORK -- Part of the thrill of "Premium Rush" is that often the actors, like Joseph Gordon-Levitt and Dania Ramirez, are actually the ones doing the cycling. The cost of that realism was the occasional accident.

When MTV News hit the red carpet for the premiere of "Premium Rush," we asked the actors to share their worst spills during filming.

Wolé Parks, who plays the rival of Gordon-Levitt's character, had a little trouble with multitasking during the shoot and served as a good reminder to stay off your phone while on a bike. "One embarrassing time, I was supposed to answer the phone," he said. "I look at it with one hand, and I kind of have bad balance. I hadn't noticed that a cab had stopped in front of me. I ran into the cab, and I fell down and scraped myself."

Not all of the characters in "Premium Rush" had to strap on the helmet and ride, but that doesn't mean they haven't had some of their own mishaps. Jamie Chung managed to hurt herself during a spin class. "I spin, and it's pretty intense," she said. "I hurt myself popping out of the pedals. It's pretty embarrassing, but I hurt myself regardless. I'm so clumsy."

Ramirez learned the hard way that riding a fixed-gear bike comes with added risk. "There's a part of the movie where I'm actually hitting a cab's side mirror with a chain, so when I hit it, the chain left my hand. Just so you know, we're riding [fixed-gear bikes], so you have to continue to pedal every single time. You can't change gears or anything. I had cages, so my feet were inside my bike. When I tried to dodge and go over to the side, because the chain was going to go into my wheel, everything just hit a pothole in New York City."

Even though they all had accidents, the cast agreed that Gordon-Levitt's on-set accident was the worst. Director David Koepp remembers the day all too well. "The worst accident was Joe's," he said. "A car cut into our lane, drove over some cones, and cut him off. He had to swerve and went off, over the back of the cab and through the back window and got 31 stitches in his arm, which was really terrifying. For a moment, you're watching the monitors, and for a moment, he leaves frame, and he's wearing a body mic, so I can hear the most horrible crash. For about 18 seconds before I could get there to see what happened, I'm thinking, 'Did I kill him? Did I actually kill an actor?' "

But despite those gory details, Gordon-Levitt played down the incident. "Thirty-one stitches," he said. "Yeah, it happens. You gotta bleed for the art."

Check out everything we've got on "Premium Rush."