He's half the man he used to be.

Matthew McConaughey looked like a skeletal shadow of himself jogging outside a gym in Austin, Tex. on Friday. In several layers of workout clothes, the actor, 42, looked alarmingly gaunt and haggard -- even more than than he did just five days earlier on a stroll with his mother, Mary.

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As previously reported, the usually muscular star's body transformation is all for an important new film role in The Dallas Buyer's Club, which tells the real-life story of Ron Woodruff, a drug addict in 1980s-era Texas who contracts HIV, and became one of the first AIDS activitists.

 "I'm playing a guy who was sick and would have loved to have been healthier but wasn't. For me, it's more of a mental thing than a physical thing," McConaughey told Us in August of playing Woodruff, who launched one of the first-ever AIDS support groups.

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Eating "small amounts" of high-protein, low-carb food, the star told Us "I'll get down to the weight I need to get to. I'm on my way, and it's what I need to do for the job."

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Still, despite the star's commitment to his craft -- he's lost about 30 pounds -- a recent online poll at Us Weekly suggested that most fans think he's gone too far: With 90 percent of nearly 18,000 votes expressing concern for McConaughey. Tell Us: Do you think he's gone too far?

This article originally appeared on Usmagazine.com: NEW PICS: Matthew McConaughey Looks Unrecognizable, Alarmingly Gaunt Leaving Gym