By Dani Nick

Philadelphia (CW Philly) — While filming The Flash, the show’s main speedster, Grant Gustin, doesn’t actually run. However, this wasn’t always the case. During an interview with Conan O’Brien, Gustin explained how filming has changed over the seasons.

“Season one we’d put me on a treadmill with a harness, and then I realized on the show that it was always like a waister shot and that my legs weren’t in frame, so they had me running for no reason whatsoever,” Gustin said.

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He proceeded to demonstrate how he moves his upper body to make it look like he is running. With the help of special effects, Gustin looks like he moves at the speed of light to viewers.

Though Gustin is an actor, who portrays a metahuman in a fictional series, he is still challenged to races in real life.

“I’m challenged to races,” Gustin said. “Never a stranger. I’ve had a good friend of mine who, to be honest is tiny and like should have assumed that I could have beat him, that I’m faster than him and then crew members, two different crew members,” he said. 

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Even without the special effects, Gustin beat his opponents.

“I’m 3 and 0,” he said. 

What do you think of the special effects in The Flash? Sound off in the comments!

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The Flash airs on Tuesday nights at 8 p.m. on The CW Philly.