Kym on David Arquette's 'DWTS' Rehearsal ADD

David Arquette's high spirits and happy-go-lucky attitude could put a smile on the face of even the grumpiest of Dancing with the Stars viewer, but his pro-dance partner Kym Johnson confesses it's a difficult task to bring focus to Arquette's seemingly never-ending supply of energy.

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"I get pretty crazy being stuck [in the dance studio] for six hours," David admits. "I start running around, jumping on the walls and everything."

Kym couldn't help but laugh as David shared stories with the Entertainment Tonight crew of his limitless energy reserve, which only seems to grow larger after hours and hours of grueling rehearsals. "He'll start noticing things in the room that I've never seen after being here for five years!"

"He'll be like, 'look at that thing up there'," Kym explained, demonstrating the smacking motion she likes to use in bringing his attention back to the task at hand.

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Recalling a particularly frustrating practice, David recalls Kym asked in jest if she could catch his "ADD," as his inability to focus was becoming contagious.

Hear more from David and Kym while they prepare for tonight's all-new episode of Dancing with the Stars on ABC. The final eight couples will be designing their dances to a theme of the eighties.