VIDEO: Jake Gyllenhaal Chats Grueling Fitness Regimen for New Film SOUTHPAW

Jake Gyllenhaal stopped by this morning's GOOD MORNING AMERICA to share details of his grueling fitness regimen to play the part of boxing champ Billy Hope in the new film 'Southpaw.' Watch the appearance below!

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ABC News' popular morning program, "Good Morning America," is anchored by Robin Roberts and George Stephanopoulos. Amy Robach is the News Anchor, Lara Spencer is Co- Anchor and Ginger Zee is the Meteorologist.

Now in its 38th year, "Good Morning America" is watched by millions of people who wake up to the show's award-winning combination of breaking news, hard-hitting interviews, exclusive investigations, cutting-edge medical information, and financial reporting. The week of April 9, 2012 "Good Morning America" was the #1 morning newscast for the first time in 16 years, snapping NBC's historic 852-week winning streak.