Sydney Sweeney is opening up about her dramatic transformation to portray legendary boxer Christy Martin in an upcoming biopic. In a new interview with W Magazine published Monday, the actress revealed she spent months training for the role, gaining 30 pounds and going up four pant sizes in the process.

Sydney Sweeney underwent intense preparation for her role as Christy Martin in an upcoming biopic, describing the transformation as "crazy." Here's what she said!