The Magic Mike stud, 35, was first linked to Demi Moore, 49, in early June after witnesses spotted them chatting and during the That's My Boy after party in L.A. But in an interview on Ryan Seacrest's KIIS-FM radio show Thursday, Manganiello assured women everywhere that "there is 100 percent zero truth" to relationship rumors.
(Moore split with Ashton Kutcher, 34, in November 2011 after six years of marriage; he had been unfaithful to her on numerous occasions, most notably with party girl Sara Leal on their sixth wedding anniversary.)
At the Samsung Galaxy S III launch in Beverly Hills later that night, Manganiello admitted to Us Weekly that he typically doesn't "care to talk about his personal life, unless it is to shoot down rumors that I'm dating someone -- like what showed up on the internet this week."
Though he was hesitant to say much more about his personal life, Manganiello -- whose engagement to model Audra Marie ended in 2011 -- was delighted to talk about his role as an exotic dancer in Magic Mike.
"You have no idea what you are in for! You are going to be speechless," he promised. "It's really to an honor to be a part of the movie, and when I found out Steven Soderbergh was directing, I was all in."
To prep for his role as Big Dick Richie, Manganiello consulted "a really good friend who was a male stripper in Dallas in the '90s" and enrolled in "stripper boot camp" with costars Channing Tatum, Alex Pettyfer, Matt Bomer and Matthew McConaughey.
"It consisted of doing body and hip rolls in the mirror for hours on end," he laughed to Us. "Funny, but I'm serious."