9 Insane Ways Oscar Winners Trained For Movie Blockbusters

6. Renée Zellweger Ate 4,000 Calories A Day (Bridget Jones: The Edge Of Reason)

Renée Zellweger scooped a Best Supporting Actress Oscar for her performance in 2003's Cold Mountain, but between the years of 2001 and 2004, her weight fluctuated considerably as part of her commitment to the smash hit Bridget Jones franchise.

In order to play Jones for both the 2001 original and 2004 sequel, Zellweger ate up to 4,000 calories per day to quickly gain weight from her traditionally svelte frame.

In-between the two movies, the actress had to hit the gym hard in order to lose weight for movies Chicago, Down with Love and Cold Mountain.

The yo-yo diet took its toll on the actress, who said, "My body is whacked by the time we finish [Bridget Jones]. It doesn't know what has happened...[Putting on weight] sounds like heaven and for two days it's bliss. Then after a week your glucose levels are going crazy. You're up and down and all over the place. It doesn't feel good, and no one wants to hear that, but it's the truth."

Was It Worth It?: All three Bridget Jones movies were huge hits and are the role for which Zellweger remains best-known. Plus, the actress mercifully wasn't asked to plump up again for 2016's Bridget Jones's Baby, so it's a resounding yes.