PIC: Justin Theroux Shows Off Super-Buff Arms!

Justin Theroux in New York City on September 12, 2012. Morgan Dessalles/ABACAUSA.COM

Jennifer Aniston is one lucky woman!

The Friends actress' fiance, Justin Theroux, 41, showed off his buff biceps while wearing a sleeveless tee in New York City's East Village neighborhood September 12. Carrying a backpack and motorcycle helmet, Theroux looked more in shape than ever before.

To stay fit, the Your Highness actor "runs a lot," a Theroux source told Us Weekly earlier this year. "He's a kind of 'train yourself' type."

While Aniston, 43, is busy shooting We're the Millers in Wilmington, North Carolina, Theroux has been spending time in Manhattan, where he's lived for more than a decade. On September 8, the tattooed screenwriter sat in the front row during the Alexander Wang fashion show at Pier 94. As director Rupert Sanders' model wife Liberty Ross stormed the catwalk, Theroux chatted with Ninja, lead vocalist of the South African rap group Die Antwoord.

Theroux, who first met Aniston on the set of Tropic Thunder, reconnected with the actress while filming Wanderlust in 2011. He popped the question on August 10, 2012 — his 41st birthday.

According to an Aniston insider, the bride-to-be would love a "destination wedding, kind of like eloping with a few friends." Though no date is set, an insider told Us, "There will be the feeling of a vacation, since that's their favorite thing to do."

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