The pair limbered up for the popular segment that sees celebrities copying the crazy moves of some tiny tykes, who lead the class.
Dressed head to toe in workout clothes, the host and his flexible guest mimicked the mini instructors, with very funny results.
Hudson, 37, and Corden, 38, kicked, crawled and shimmied their way across the dance studio as the energetic kids pulled off their best moves.
Before they began, Corden gave the Fabletics founder a stern warning.
“I know you think you’re in shape, but these instructors are going to beat you down,” he said. “These instructors are a nightmare. They made Dwayne Johnson cry. The Rock, they made the Rock cry.”
Hudson seemed to take it all in stride and happily leaped and twirled, while Corden struggled to keep his form.
The tiring session ended with a cooldown that involved a nap and some juice.
Check out how Hudson did in the video above.
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